Category: Garden

Posts about gardening and related topics, such as canning and maybe other aspects of food preservation.

Post G23-003: Garden plan, 2023, step 1.

As my store-bought organic potatoes chit (sprout), in anticipation of planting on St. Patrick’s day, I am in the process of figuring out what else I’m going to grow this year.

In a surprise move, I’m going to take my wife’s advice and … wait for it — only plant stuff that we actually like to eat.

Then it occurred to me that I should only plant stuff that the deer don’t like to eat.

Now that I was surfing that intellectual tsunami, I went out on a limb by saying that I probably don’t want to plant stuff that my local bugs like to eat.

Finally, drafting in the wake of that runaway 18-wheeler of brilliance, maybe I should avoid plants that are susceptible to diseases frequently found in my garden.

Fantastic.  Easy-peasy.  Planning accomplished.

I just need to fill in the details.

Unfortunately, when I do the Venn diagram of those four insights, I’m left with:

And I’m not all that sure about the red one.

(Plus, as I understand it, that “guy” on the left is now part of a lefty-liberal plot for the emasculation of America.  Pink ears, blue shoes — that’s certainly a mixed message, but that’s the way the libs go after it.  Slow rot.  Next thing you know, they’ll be taking away his angry eyes.  And then they’re coming for your potato cannon and spud gun!!  You’ve been warned!!!)

Time for a bit of a rethink.  More soon.

 

 

Post G23-001: Tomato sauce from frozen tomatoes

One of the joys of gardening is coming across fresh-frozen produce, in the dead of winter, that you squirreled away last summer.

In the Spring of 2022, after determining that freezing was the most energy-efficient way to preserve tomatoes (as long as you have room in an already-running freezer), I froze a bag of early-season “4th of July” tomatoes. Washed them, cut their tops off, put them in a vacuum-sealed bag, and froze them.  (Then sealed the bag, after they had frozen.)

Source:  Post G22-010.

The clincher for me was finding out that frozen tomatoes will slip right out of their skins.  If you’ve every tried to peel a lot of tomatoes, you know what a plus that is.

That’s what I’m doing, in the video above, with the thawed tomatoes.  They already have their tops cut off, they’ve been thawed, and they do, indeed, slip right  out of their skins.

I learned that trick from the blog “from the family with love“.  (You can see her video of peeling frozen tomatoes at this youtube URL).  But, you know, sometimes, there is room for doubt until you actually do it with your own hands.

As a bonus, freezing them (after removing the tops) separates out most of the liquid.  When I pulled the now-thawed tomatoes out of their vacuum-seal bag, roughly half of the output was tomato solids, half was tomato water.

Obviously, after freezing the texture isn’t good enough for eating out-of-hand.  But for a quick batch of tomato sauce, or for adding some chopped tomatoes to a stew, these are fine.  I’m making sauce, so I ran a stick blender through it to pulverize the seeds before reducing it down.

I might even go so far as to say that these are nice.  Compared to canned tomatoes, freezing seems to preserve more of that “fresh tomato” taste. I’m vaguely guessing it preserves more of the aromatics that are lost in canning.

So there you have it.  Wash them, cut the tops off, freeze, then seal the bag their are in.  Thawed half a year later, they are a little taste of summer to enjoy in the dark of winter.

Post G22-065: Round, brown, and slightly moist most of the time.

 

But few people have one.  And that’s a situation I’m trying to change.

A couple of months ago, I put away some seeds from the pawpaw trees in my yard, with the idea of starting and giving away pawpaw seedlings in the spring.  Preserving viable seeds turned out to be quite a process (Post #G22-062).  After a thorough cleaning, the seeds need to be kept moist, and kept cold over the winter.  So a couple of plastic bags of seeds-in-damp-potting-soil have been living at the back of my fridge for the past two months.

Today it was time for a mid-season checkup. 

They’re still brown (no evidence of mildew or fungus).  And they’re still damp, though it’s clear that they have dried out somewhat, so I’m going to top them off with a bit of fresh water.  (In hindsight, I should have weighed them before I tucked them into the fridge.)

But, in general, things are proceeding according to plan.

Except that I don’t actually have a plan.  I started this in response to a request for pawpaw seeds.  I noted how difficult it seemed to be to come by pawpaw seedlings locally. And pawpaws are the only known host of the zebra swallowtail butterfly.

So when you get right down to it, my entire rationale for doing this is butterflies (aw!). 

And thus I have fallen into the classic charismatic megafauna trap.  As humans, we focus on saving animals that are attractive (pandas).   Or noble-looking (elephants).  Or have cultural context (bald eagles).  Or, in this case, cute, and the Virginia state insect (zebra swallowtail butterfly).

The dead of winter is the perfect time to step back and take a more objective look at this effort.  Given that we’re in the middle of the great insect apocalypse, and given that growing trees in suburban yards is more-or-less a zero-sum game (if not a pawpaw, then some other tree), what is it, exactly, that I’m hoping to accomplish.

Is propagating pawpaws the smart thing to do?   Aside from the technical gardening challenge of doing this, and helping one insect (because it’s so cute!), is this really the best use of my time?

A summary of expert advice for an insect-friendly urban environment.

As my first attempt at being somewhat more systematic, let me use Google to find seemingly-serious websites offering advice on how to create an insect-friendly urban environment.

To frame that properly, I need to state clearly that urbanized areas constitute only a tiny fraction of U.S. land area.  So, from the outset, this list is going to be oriented toward personal actions that residents of urbanized areas may take.  My little survey clearly is not going to have the right “weighting” in terms of global impact, because those urbanized areas constitute such a small part of the entire U.S. insect habitat.

You can look at that any number of ways, and arrive at the same conclusion.  The U.S. Census has a formal definition of what it considers to be an urbanized area:

Source:  Census data via University of Texas.

Bloomberg has a nicely detailed summary of U.S. land use.  You reach much the same conclusion from that as you do from the map above.  Urban areas account for a few percent of the total land area of the U.S.

Source:  Bloomberg, Here’s How America Uses Its Land,By Dave Merrill and Lauren Leatherby,

So, almost beyond a doubt, policies or actions applicable to the other land categories will have a much larger impact than what gets done in urbanized areas.  Pasture/range, forest, cropland, and parks (and other special-use lands) vastly outweigh urban areas in terms of insect habitat.

The easiest way to quantify that is to focus on the diagram above.  Roughly speaking, there’s one acre of crop land and two acres of pasture/grazing land for every resident of the U.S.  Most of the production from that land is consumed domestically.  Adults consume more than kids.  If I had to guess, I’d guess that growing a year’s food for two U.S. adults takes up at least six acres of land.  Compare that to my suburban lot, and, arguably, what I choose to eat is going to matter a lot more than how I landscape my yard.

But you do what you can.

For urbanites.

That said, below I have tabulated the advice most commonly offered to Joe and Jane Urbanite, to help protect and preserve the insect population.  This is literally the first nine reputable sources that showed up in a simple Google query of best things to do to help insects.  The full tables may be a bit tough to read, so scroll down for just the good parts.

Just the useful bit:

When I start from this perspective, I’m pretty sure that displacing other species of backyard trees, in favor of pawpaws necessary for a single butterfly species, is probably not the most effective thing I can be doing to help beneficial insects survive in my yard.

#1:  Overwhelmingly, the first piece of advice is to reduce the area of your lawn, in favor of … well, just about anything else.   Eight of nine sources said some version of that.  Minimally, don’t mow it.   Maximally, return it to more-or-less a wild area.  Maybe plant it with wildflowers.  Maybe plant it with insect-friendly plants.

I think I’m going to take this one to heart next year, as I have a large section of my back yard currently covered in black plastic, trying to kill the weeds.  And a whole lot of saved flower seeds.  I think that’s all going to become a flower bed next year.

#2:  Skip the pesticides and herbicides.  I think I have that one knocked.  The more I grow in my vegetable garden, the less inclined I am toward any type of insecticides.  Herbicide?  I spell that h-o-e.

#3:  Address your outdoor lighting. I had no idea this was quite so much of an issue.  Everyone gives the same advice.  Minimize outdoor lighting.  And if you use outdoor lighting, go toward the red/yellow/amber spectrum, not white.  Apparently, there is some truth to the idea that old-fashioned yellow bug lights attract fewer bugs.  What also appears true, however, is that the switch to LED street lights. however good that is from the standpoint of reducing energy consumption, is a step backward in terms of harm to the insect population.   Apparently, those old fashioned yellow high-pressure sodium lights were reasonably benign, compared to the white light issued by LED or mercury vapor/halide lamps.

For me, this is fixable.  I have exactly two small outdoor lights.  Both have white bulbs in them.  I’ll swap those for bug lights, and problem solved.

#4:  Create bee nests, bug hotels, and other protected habitats.  Or, alternatively, just leave the edges of your yard looking like crap all the time.  That works for me.  I now have a great excuse for leaves, branches, pine cones, etc. along the margins of my yard.  It’s not sloth, it’s environmentally sound policy.  Plausibly the wilder it looks, the more insect-friendly it is.

But you can also buy bits of made habitat.  I bought one of those solitary-bee or mason-bee nesting boxes in Spring 2016.  Never touched it.  Here’s how it looks this morning:

To me, that looks like an underwhelming amount of new-bee production for six years.  A lot of the tubes remain untouched.  Maybe a half-dozen have clearly released a live bee, as evidenced by the hole in the end of the mud.  A few more might hold bees that will emerge this spring.  That said, those bees will re-use those tubes, so it’s not clear exactly how many bees this investment produced. Or, for that matter, whether those bees would simply have laid their eggs elsewhere, absent this cute little device.

That said, I already own a couple, so I guess I’ll get the refill tubes, clean them up, and re-hang them.  What could it hurt?

I’m going to stop there, except to note that planting native plants (such as pawpaws) is pretty far down the list.  And so, as I had begun to suspect, it’s likely that going to all this effort to produce pawpaw seedlings is not very efficient.  Laboriously saving the seeds, to produce the seedlings, so that others may displace some trees in their yard with pawpaws, so that the zebra swallowtail has a place to lay eggs … that’s a positive thing to do, but it should hardly be first on the list.

Best guess, after fixing my outdoor lighting, the single smartest thing I can do is transform large portions of the edges of my yard to wildflowers.  Around here, it takes considerable effort to keep “wild” patches of yard from being overgrown with less desirable plants.  So it’ll take some doing to get a setup that has any hope of maintaining itself, even if I mow it once a year to keep the trees down.

After that, it’s probably a question of being pickier about what I eat.  I’m not sure about the extent to which eating organic produce actually avoids use of pesticides, rather than merely substitutes some classes of pesticides for others.  But I am pretty sure that foods vary widely in terms of the average amount of pesticide and herbicide used per edible calorie.  I think my next step is to see if research can generate any reliable information on that.

Post G22-064: Judgement Day, the Seedy Edition.

 

Or Judgment, depending on which style guide you follow.

When I started trying new varieties of plants in my little backyard garden, I did not quite grasp one obvious consequence:  At some point, you have to thin down your seed collection. 

Left to its own devices, my shoebox of seed packets exhibits reverse Darwinism: Survival of the un-fittest.  It’s not merely that I end up with far too many packets of seeds.  It’s that the long-term survivors are the duds — the ones I didn’t want to plant again.  By contrast, plants with desirable traits are removed from my shoebox gene pool, because I planted the seeds and grew them.

It’s a nice metaphor for much of the junk in my life.  The shirts I wear every day eventually wear out.  The ill-fitting and the ugly remain until I haul them off to the thrift shop.  The low-fat, low-salt cottage cheese slowly expires at the back of the fridge.  But somehow my pantry has never held a bag of potato chips beyond its expiration date.

Why is this seed pack a loser?  Let me count the ways.

Above: The starting point.  It’s not quite as chaotic as it looks, because I have them sorted into categories.

1)  I just ain’t gonna grow that vegetable any more.

Here, the varieties themselves are blameless.  It’s mostly that nobody wanted to eat them, even if I grew them well.  Or, in a few cases, that, plus they seemed to be more trouble than they were worth.

Maybe I’ll try to give these away.  There’s nothing wrong with the seeds.

  • Radishes
  • Turnips
  • Kale
  • Swiss Chard
  • Ground cherry

2) I ain’t gonna grow that variety any more.

Some of these just didn’t grow well.  Some didn’t taste like much.  And, to be clear, I’m tossing some not because they are intrinsically bad but because I could use the same space for better varieties.

2.1) Tomatoes

 

These all grew, but were disappointing for some reason.  Some, I couldn’t tell when they were ripe.  Others lacked taste.  Some had poor yields, possibly due to operator error.  But mostly, they aren’t themselves bad, it’s just that there were better varieties for my garden conditions.

2.2)  Squash

At the end of the day, I’m sticking with a handful of tried-and-true varieties of winter and summer squash.  As with the tomatoes above, the ones pictured here  just didn’t do as well as other varieties that I planted.

From now on, I’ll do a couple of varieties of winter squash (Dickenson pumpkin, Waltham butternut squash), a couple of varieties of summer squash (prolific yellow straightneck, black beauty zucchini), and call it a day.

2.3 Cucumbers.

I’m giving up on cucumbers for the time being.  Cucumber beetles are now endemic to my garden.  I’m not willing to use the strong toxins it would take to get rid of them, and none of the varieties above is sufficiently resistant to bacterial wilt, spread by cucumber beetles.  In addition, my attempt at growing parthenocarpic cukes under insect netting failed.  I’m giving it a rest next year.

Conclusion

With that thinning, everything now fits in one plastic shoebox.  In theory, I ought to vacuum-seal these seeds, so they’d last longer.  In practice, I tend to use them up before they start failing to germinate.

This has been an odd post, in that all I talked about is the stuff that didn’t work.  But every once in a while, you have to clean house.  By its nature, that has to focus on the duds.

Post #1635: First frost

 

Source:  Analysis of historical weather data from NOAA.

Stealth frost

It looks like we’re going to have a few nights with freezing temperatures this week, here in Vienna, VA.

I’ve been doing a few chores in and around the garden to get ready for that.  The most important of which was moving a large potted lime tree into the garage.  Even a touch of frost and that would likely die back to the ground.  I’ve also drained all the water barrels, and I’m bringing hose timers and other frost-sensitive objects inside.

This means it’s also time to redo my prior analysis of trends in first frost.  It’s been unseasonably warm in the East, so it would be no surprise if this year’s first frost were a bit later than usual.

But when I actually looked at the data, I got a surprise:  Dulles Airport (my standard for this frost analysis) recorded a frost about three weeks ago, on October 21.  I missed that, and clearly we didn’t get a frost in Vienna, based on (e.g.) the fact that my okra plants are still alive.

That said, on average, first frost in my area is now about 20 days later than it was in the 1960s.  As you can probably see from the graph, virtually all that change has been in this century.  That couple-of-weeks shift in the first frost date appears to be a fairly widespread phenomenon (per this reference).

That’s consistent with the continued northward shift of the USDA hardiness zones.  They update those every so often, using more recent historical weather (i.e.) climate data.  With the most recent up date (2012, using the 30 years of weather ending 2010), most of the zone boundaries slid north, compared to the prior map (using the 30 years ending in 1990).  Apparently, the average rate of travel of the hardiness zone boundaries is reported at 13 miles (north) per decade (per that same reference).  That varies widely, as zone boundaries at the coast shift more slowly, due to the moderating effects of ocean temperatures.

In any case, it will be sometime around 2040 before Vienna, VA makes it into Zone 8 — or Zone 8 makes it to Vienna — take your pick.

Source:  NOAA, via the New York Times 

So I guess it’s still a bit early to expect climate change to save me from these frost-related chores.  But give it enough time, and we our descendants our descendants, if any, will have no problem growing palm trees around here.

As was true at last year’s first frost date (Post G21-057), indoor relative humidity remains high.  That said, I’m keeping an eye on it, and when it drops below 40%, I’ll start running my humidifiers.  I summarized why that’s important for prevention of respiratory infections in Post #894.

Source:  American Society of Heating, Refrigerating and Air-Conditioning Engineers

Post G22-063, 2022 final garden wrap-up

I’ve picked the last of my peppers, stripped the green tomatoes from the vines, set them up to pickle (shown above).  All that’s left growing is a bit of stunted lettuce and spinach, and a few onions left to overwinter.

As I get my garden beds ready for the winter, I’ll summarize what I think I learned in my third year of being a serious vegetable gardener.  Let me arrange this from choosing seeds to preserving the harvest.

Choice of varieties. 

This isn’t everything I grow, it’s just plants where I had something to say.

For tomatoes, I settled on growing four broad classes.  Varieties are shown in Post G22-001. 

  • Early season/cold tolerant,
  • Heirloom “extra tasty” tomatoes,
  • Paste (for drying), and
  • Heat-tolerant (to keep yields up in August)

Early-season/cold-tolerant tomatoes were a total winner.  I had tomatoes by June, and those plants continued to bear through October (Post G22-025).  I judged the overall winner to be Fourth of July, a hybrid from Burpee Seeds.  I’ll plant that again next year.

OTOH, my other tomato choices were flops.  Two (paste, heat-tolerant) were due to operator error (deer damage, poor location, planted too late.)  But of the three heirloom tomatoes I tried, the only one I will keep is Cherokee Purple.  That produced a decent yield of consistently tasty tomatoes.  For the other two (Aunt Ruby’s German Green, Chocolate Stripes), I simply couldn’t guess when they were ripe. I won’t grow those again (Post G22-051).

Ground cherries.  I tried and rejected ground cherries (Post G22-029).  They grew with no fuss, as advertised.  But yield was tiny and harvesting was a pain.  Plus, as it turns out, I don’t much like them.  Mine, at least, were not sweet.  I’m not growing them again.

Summer squash and cucumbers.   I have a terrible time growing these due to insect pests (squash vine borer (Post G27), and cucumber beetle (various posts).  For squash vine borer, I had mixed success spraying with Spinosad (Post G21-044).  That’s only bulletproof if you stake the squash vines up, off the ground, and it’s a lot of work in any case.  For cucumber beetle, I never found a method of killing them that I was comfortable with, because I don’t want to use (e.g.) Sevin or similar pesticide dusts.  Nothing I tried worked at all, including methods that get a generally good reputation on the internet (such as yellow sticky traps).

This year I tried growing parthenocarpic varieties under insect netting (Post G22-013, Post G22-050).  The upshot is that the “parthenocarpic” part didn’t work out, but that growing under netting is a pesticide-free way to avoid the worst of the squash vine borer.  Timed right, I end up with large, flowering summer squash by August 1 or so.  At that point, there’s only an occasional squash vine borer visiting the garden, and I can take the netting off and get some summer squash.  For cucumbers, by contrast, this didn’t work at all, because the cucumber beetle appears to be a year-round pest in my garden now.

I’m  not sure if I’m going to try growing under netting again, or not.

 

Winter squash.  I experimented last year, but I’ve settled on good old Waltham Butternut squash, and on Dickinson pumpkin (which, despite the name, size, and shape, is just a gigantic winter squash, and tastes more-or-less exactly the same as butternut squash.)  These are pretty much hassle-free, although I do wrap the pumpkins in floating row cover to keep the squirrels confused.  I’ll plant these again next year.

Potatoes.  I finally figured out exactly why you typically can’t use store-bought potatoes as seed potatoes (Post G22-004).  And yet, sometimes, you can.  The answer is organic potatoes can’t be treated with the most potent and toxic sprout inhibitor.  So, either buy certified seed potatoes, or plant organic potatoes from the grocery store.  Chit early and often.  Consider no-dig planting if you’ve got money to burn and/or a cheap source of straw (Post #1073).

Sweet potatoes.  God’s gift to the lazy and untalented gardener.  Buy them from the store in late winter, sit them in some damp potting soil until they sprout, plant the slips (sprouts).  Water well.   If you want more, cut a foot off the ends of some vines, strip off most of the leaves, and plant those.  Nice to have a food plant that’s so aggressive it can strangle the weeds.  Definitely planting again.  No idea what variety I’m planting, because it’s whatever is in the grocery store.

Beets, turnips, radishes.  Nix.  I’m just giving up on these.   I can’t seem to get a decent-sized root in my soil, and I’m the only one in my family who will eat them.

Eggplant.  Nix.  Grows well, nobody else in my family will eat it.  Skipping that next year.

Heavy-hitter Okra.  This was a disappointment.   I grew about ten okra plants, of the “heavy hitter” strain.  These are supposed to produce multiple flower heads per plant and to be extremely productive.  What we actually got was some nice-looking plants with mediocre production.  Throughout the summer, we managed to get one pod per two plants per day.  I’m going to try a different strain next year, but I suspect that I’m just going to have to plant a field of okra if we’re ever going to have a surplus of it.

Seed starting

Fluorescents are obsolete.   I had been using a two-bulb four-foot shop light as a grow light, for staring plants inside.  This year I “rewired” it (basically, gutted it) and (eventually) successfully installed LED replacement bulbs (Post G22-003).  The LEDs use about half the electricity that the fluorescents used.

Window box is best.  That said, the cheapest source of grow light is the sun.  I’m not very good at using a cold frame — I typically end up frying my plants on a sunny day.  So I made a cheap, temporary window box out of some clear plastic totes (Post G22-003).  That worked fine and was climate-controlled.

Dump the peat pellets, use paper bags instead.  For years, I have started seeds using peat pellets.  These are convenient, and hold together well as you move your seedlings from place to place.  But a couple of things happened this year that have made me change my mind on peat pellets.

First, I had an exceptionally productive year for winter squash.   Easily four times the yield I’ve had in any prior year.  Here’s a picture of some of what I harvested.  Those butternuts came from just four Waltham butternut vines.

But the only thing I did differently this year was to start those squash seedlings without using peat pellets.  I started them in cups, then moved them to doubled-up paper lunch bags (Post G22-012, Post G22-017). As I pulled up those vines, this year, I noticed that they seemed to have exceptionally well-developed roots.

This got me to wondering whether those peat pellets inhibit root formation.  I stopped using peat pots long ago for exactly that reason.  I’d pull plants up at the end of the season, only to find that they were root-bound inside those un-degraded peat pots.

As I pulled up my late tomato vines, I decided to compare those that had been started in peat pellets, and those that had been started in cups of potting soil.  These are plants of about the same size and that were started at the same time.

These were both photographed at arms length.  Note that the peat pellet is still largely intact (left).  And that the plant grown without using a peat pellet (right) has an obviously much more developed root structure, with a far longer tap root and longer side roots as well.

As it turns out, I am not the only person to have noticed this.  If you Google peat pellet root bound, you’ll find lots of stories and pictures showing plants that became totally root bound in a peat pellet.  Some then suggest cutting up the mesh that holds the peat pellet together, but to me, that kills the main advantage of planting the intact peat pellet, which is that you avoid transplant shock.

The upshot of this is that I’m tossing out my peat pellets, and starting plants in doubled-up paper bags from now on.  Those bags get quite fragile by the time they get planted, but that’s the whole point.  You want them to be just at the point of falling apart when they are put into the ground.

Timing, frosts, and days to maturity

Fall garden flops.  Two years in a row now, I’ve followed standard gardening advice and planted some fall crops in the garden.  I’ve direct-sown some greens and such.  And two years in a row, that’s been a total flop.  Here’s the writeup for last year (G21-057).  It’s pretty much ditto for this year.

The upshot is that while I can direct-sow seeds in late August in Zone 7, it’s probably going to be a complete waste of time.  As the days shorten and the temperatures cool, plants begin to grow not just more slowly, but much more slowly.  I did the analytics on this in Post G22-061.

The upshot is that you can either put in some sort of poly tunnel or greenhouse, or you can start your fall crops in pots in July, so that you are planting out month+ seedlings.   What I can’t do is direct sow (e.g.) lettuce and spinach at the end of August and expect to have usable yield.

Frost protection alone isn’t worth it.  This year, I nailed down the ins and outs of frost protection.  Aluminized fabric or space blanket radiant barrier works great (Post G22-005).  Mason jars (and some types of plastic) work great, because they are radiant barriers (Post G22-006).  Some other plastics work, but polyethylene sheeting or floating row cover has no impact.  Basically, those are worthless for frost protection (Post G22-005).

But this year, as I was hustling and putting my plants in early and protecting them when there was a threat of frost — it occurred to me that this is largely a waste of time (Post G22-009).

Why?  See Fall Garden Flops above.  If it’s that early in the spring, when it’s cold out, plants grow at a snail’s pace.  You put in a huge amount of effort to keep those plants from freezing, and your reward is a tiny head start on the gardening year.

To get a head start on the growing season, it seems like it’s far smarter to keep growing your seedlings in some sort of protected (i.e., warmed) space, then plant those much larger seedlings into the garden only after things have warmed up.  That means setting up some sort of poly tunnel with frost protection — to raise daytime temperatures for the plants and prevent nighttime freezes.  Or keeping your seedlings in some sort of cold frame/window box arrangement until they are much older and larger than you would normally grow them.

In any case, my take on it is that planting early, into a cold garden, and hustling to provide frost protection, is all pain and (almost) no gain.  I’m not going to do that next year.   If I need frost protection, it’s too early to plant.

Days to maturity does not tell you much.  I worked through all the details on what “days to maturity” means, as printed on seed packets, in Post G22-025. The reality is that a) that figure is for ideal growing conditions, b) that’s just the date on which under ideal conditions you can pick your first ripe crop, and c) in spring and fall — when that figure really matters — days to maturity will be vastly higher than the number cited on the seed pack.  See Fall Garden Flops above.

The bottom line is that if you start from your fall first frost date, and count backward by “days to maturity”, you are nowhere near the correct date for planting seeds for a fall crop.  You have to plant them much, much earlier than that to be able to expect to harvest anything.

Water

Irrigation.  For a little home garden, it turns out that an effective irrigation system can be incredibly simple, quick to install, reasonably cheap, and will work with rain barrels or city water.  See post G22-037 and further references in that post.  I can’t believe I went through two years of carrying buckets all over the garden.  If I had it to do over, I’d put in irrigation from the start. 

Hose timers.  These always seem to fail after a few years.  With my last failure, I did an autopsy to figure out why they die, then modified my new timer accordingly (Post G22-028).

Rain barrels.   I think rain barrels are a good thing, and I have a bunch of them.  But no matter how many I have, I always seem to run out of water anyway.  And I end up using city water, run through an activated charcoal filter to remove the chloramines.

So I did a “micro-simulation” model of a rain barrel system, using the actual historical rainfall data for my area (Post G21-043).  And, sure enough, practically speaking, you are always going to run out of water.  As it turns out, for a small garden like mine, the first few rain barrels do a lot of good, and then the benefit per additional rain barrel decreases rapidly.  And, don’t kid yourself that you’re doing much for the environment by using rain barrels.  I think that if I’d known this from the start, I’d have put in a couple of rain barrels and called it quits. For a few hundred square feet of garden beds, a large rain barrel system is mostly a waste.

Staking, mulching, weeding.

Sprawl technique for tomatoes (Post G22-018).  That’s a big No on that one.  They grow fine.  In fact, the probably grow better if allowed to sprawl than they do if staked, because they put out secondary roots.  But harvesting is a nightmare, and you lose a lot of the crop to bugs.  I used the sprawl technique this year because I had an injury that made it hard to get around.  I’d never do that again.  I’m staking and/or caging my tomatoes from now on.

Oh, and sprawl technique with green tomatoes?  Dumb squared.  Sprawl technique with black plastic mulch, in Virginia summer?  Tomatocide.  Just don’t go there.

Woven black plastic ag fabric instead of mulch. I gave this a try this year, again because I had some problem getting around in the spring, and I figured this would be a labor-saving measure. 

I see this being used all over YouTube.  I couldn’t quite figure out how plants could possibly handle the heat stress of all that black plastic with the sun beating down on it.  Turns out, by and large, mine couldn’t.  Some plants were just outright killed by the heat.  Some were stunted.  Some — mostly beefy upright plants like okra — handled it OK.

In the end, I’d say that it’s OK if you put this down, then spread straw or other light-colored mulch on top.  It’s OK if you use it as straight-up weed blocking fabric.  It probably works OK if you’ve got enough foliage to keep the black plastic cloth in the shade.  But (e.g.) planting peppers, tomatoes, cucumber, and squash seedlings through holes in woven black plastic was simply a mistake.  Those that the heat did not kill outright clearly appear to have been heat-stressed anywhere any part of the plant touched the plastic.

I don’t think I’m going to use that again as anything but weed-block ag fabric.  I don’t think I’ll try to grow my seedlings through it.

Weeding.  I looked into numerous organic weed killers, and decided that I might as well just use a weed-whacker (Post G22-046).  With one exception, organic weed killers (e.g., strong vinegar) are burn-down weed killers.  They kill the top of the plant, but not the roots.

I also tried using bamboo leaves as a natural weed killer, with inferior results (Post G22-060).

If nothing else, I gained a better understanding of why people use Roundup in their yards, even if I won’t touch the stuff.  If you want to kill a plant roots and all, you don’t really have any good organic choices.

Pests and diseases.

Electric fence for deer.  After years of trying various deer-deterrent devices, I rage-purchased the equipment to set up a small, portable electric fence (Post #G22-018).  These are reasonably cheap and ridiculously easy to set up.  The “wire” is more of a twine with embedded metal fibers.  You run that through plastic step-in posts.  You’ll need to pound in a grounding rod, that’s just about the only work involved. And you’ll need to be able to run an extension cord to where the charger is attached to the fence.

Deer damage effectively ceased for as long as I ran it.  Wish I’d thought of it sooner, and this is now a permanent part of my backyard suburban gardening setup.

I also run a Yard Enforcer motion-activated sprayer.  This works, with a few caveats.  It tends to trigger off randomly when faced with bright sunshine on broad, fluttering leaves.  And the hose connection began to leak until I replaced the original cheap vinyl hose gasket with a standard 10-cent rubber hose gasket.  Otherwise, it shows no signs of deterioration after one season of use.  And the deer will stay out of the area it sprays.

Otherwise, I have retired the rest of my arsenal of deer deterrents.  Search for that category on this website if you want to see what else I was using.

Wrap your pumpkins to keep the squirrels off (Post G30).  For the second year in a row, I wrapped floating row cover around my pumpkins.  This appears to work perfectly to keep the squirrels from gnawing on them.  That’s now a standard part of what I do when I grow pumpkins.

Powdery mildew.  The first year I gardened, I had to put in the time just to learn the lingo (Post G15).  Because, as it turns out, most commercial treatments for powdery mildew don’t actually kill powdery mildew (“eradicants”), they only claim to help prevent its spread (“protectants”).  Next you have to realize that virtually no home-remedy type powdery mildew treatments work (Post G19).  Despite having people swear by them in various internet posts.  Or, at least, did not work on whatever strain of mildew I had in my garden.  Finally, once you do come up with something that will kill powdery mildew, what you find is that a) you have to keep spraying it, and b) what you end up with is a heavily damaged plant anyway (Post G20).

That learning is summarized in Post G20.  The upshot of all that is that you ideally want to spray to prevent powdery mildew, not to try to cure some that has already set in.

I tried to test a couple of preventatives this year, one a commercial copper-based spray, the other a weak citric acid solution (Post G22-039, Post G22-040).   Nature did not cooperate, in that I didn’t ever get significant powdery mildew in the garden until very late in the garden year.  At which point, I can certify that weak citric acid solution does not kill existing powdery mildew (Post G22-060) .

French marigolds.  I’ve bought a lot of “deer proof” flower mixes.  And yeah, you can get some flowers, and yeah, maybe the deer won’t eat some of them, even if they are desperate.

But let me tell you a few things about french marigolds:

  • They form spectacular masses of flowers.
  • Native bees and some butterflies love them, based on my observation.
  • They last through the end of fall.
  • They are tough as all get out, and easily out-compete with the weeds.  To some extent, they become the weeds.
  • They stink when disturbed.  I mean, really stink. Which I think explains the next point.
  • I’ve never seen even the slightest indication of deer damage.
  • The seeds are easily saved.

 

 

Food Preservation

Vinegar pickles do not require salt.  If you are making a traditional vinegar-based pickle, the salt is there solely for flavor.  It it not necessary for the preservation of the food.  Accordingly, I tried making a sodium-free vinegar dill pickle.  The results were … OK.  Edible.  Definitely pickle-like.  I’m undecided as to whether I’d do that again, but for sure, I can’t take the high-salt diet one gets with home-canned vinegar pickles following a traditional recipe.  (See Post G22-031, Post G22-032, Post G22-036).

FWIW:  Neither pickle crisp (calcium chloride) nor soaking the cucumbers in ice had any impact on the crispness of the pickle.  Based on my final batches, you can replace salt with salt substitute measure-for-measure in a vinegar pickle recipe and get a reasonably salty-tasting pickle without significant off notes.  And it definitely helps to replace about half the vinegar acidity with citric acid acidity, following standard canning formulas as described in the posts above.  Finally, because these salt-free pickles tended to have a somewhat tough skin, you get a better product processing them as spears rather than as whole pickles.

Freezing is the most energy-efficient way to preserve tomatoes if and only if you are going to be running that freezer anyway.   That’s the gist of Post G22-010.   It is also by far the easiest.  And the skins slip right off the tomatoes afterwards (same post).

These days, I mostly preserve them by making tomato sauce on the stove, then freezing that in vacuum-sealed bags.  FWIW, my process is as follows:

  • Pressure-cook tomatoes for a minute or two, followed by natural pressure release.
  • Run the results through a Foley mill to take out skins and most seeds.
  • Boil that down to sauce consistency.
  • Place in vacuum bags, freeze, then vacuum-seal the frozen sauce.

I’ve stopped making tomato sauce in a crock-pot because it takes forever and is energy inefficient.  A crock pot is a poor device for reducing reducing tomato juice down to tomato sauce.

An ideal garden setup, based on three years’ experience.

I threw my garden together in the middle of the COVID-19 pandemic, as a way to get some exercise, and have something to do.  I set the whole thing up out of recycled materials, including a bunch of coroplast political protest signs that I had printed up for use in the Town of Vienna, VA, and some bamboo I had cut down in my yard (Post G05).

If I had to do a raised-bed garden over, from scratch, I would:

  • Orient the bed(s) east-west, for best access to sun.
  • Have one long bed, about 3′ deep from front-to-back.
  • Have a permanent trellis on the back of the bed, to stake up plants.
  • Have 1/2″ irrigation pipes installed at the surface, before planting, run to the nearest tap or water barrels.
  • Have an electric fence permanently mounted around the bed, to deter deer.
  • Accommodate a polycarbonate panel or other method for creating a temporary spring cold frame/autumn season extender.
  • Accommodate insect-proof netting, as needed.

I am still not quite ready to go full-on to growing in a greenhouse.  There are advantages to that, but any greenhouse I could build would end up being one great big disposable, as the various plastics broke down.

I think that, on this forthcoming re-build, I’m looking for something a bit more permanent, a bit less disposable, and something that incorporates all the varied temporary structures that I’ve set up over the past three years of gardening.

Post #1612: CO2 emissions from gas versus electric leaf blowers.

Source: Xerces Society for Invertebrate Conservation

To be clear, I think the right thing to do with your fallen leaves is to leave them alone, to the extent that you can (Post G22-034).  But if you’re going to use a leaf blower, how do gas-powered ones compare to electrics, in terms of generating C02 emissions?

Bottom line:  7-to-1.  At Virginia’s current electrical generation mix, a gas-powered leaf blower produces about seven times as much C02 emissions as an electric leaf blower.  I show the calculation below.

In part, that’s because the grid just keeps getting cleaner.  A couple of decades ago, the difference would have been more like three-to-one.  But mostly that’s because small two-stroke engines, as used on leaf blowers, are inefficient.

Note that this 7-to-1 ratio is just for C02.  In terms of total air pollution, gas powered leaf blowers stack up far, far worse compared to electrics.  In particular, smoky two-stroke gas engines produce huge volumes of unburned hydrocarbons, as anyone who has ever seen and smelled the exhaust from a two-stroke can attest.

To be clear, leaf blowers don’t use enough gasoline to matter, in terms of our annual C02 emissions.  They are a drop in the bucket.  And not that there aren’t a lot of other reasons to skip leaf blowers entirely, let alone gas-powered ones.  But this is a statistic that I wanted to pin down.  So here is the calculation, with citations as to source.

Background

My wife asked me a simple question today regarding gas-powered versus battery-powered leaf blowers.  How do they compare in terms of C02 emissions?  I did a quick back-of-the-envelope and got numbers that didn’t appear credible.  So I decided to do a more formal calculation, with the metric being pounds of C02 produced per 100,000 cubic feet of air moved.

It’s already well-established that gas-powered leaf blowers produced a tremendous amount of air pollution, per amount of work performed.  That owes mainly to the use of small two-stroke engines.

No shock there — these are the engines where you mix the oil with the gas, and burn that mixture to produce a smoky blue exhaust.  That exhaust is every bit as dirty as it looks.  You can look that up anywhere, and as far as I know there’s more-or-less zero disagreement about that.  Here’s what appears to be a fairly sophisticated test (reference Edmunds).

In terms of pollutants (e.g., unburnt hydrocarbons) and such, that’s the pretty much the end of the story.  Except to note that a part of the resulting air pollution is black carbon, which is increasingly being recognized as a major contributor to global warming (See Post G22-058).  So, these two-stroke gas engines contribute to global warming beyond their emissions of C02 alone.

But my question was in terms of C02 emissions.

In absolute terms, obviously, the gas consumed in lawn care is a drop in the bucket, compared to the gas consumed by cars and trucks.  (So, priding yourself on using an electric mower, while you drive an inefficient car, is straight-up greenwashing, in terms of impact on C02 emissions.  It might ease your conscience, but in the grand scheme of things, your lawn mower is rounding error in your household carbon budget.)

That said, just exactly how do the C02 emissions compare, between gas and electric leaf blowers?  My first rough cut seemed to say that gas leaf blowers produced vastly more C02, compared to electrics, than gas cars did compared to electric cars.  (Which, for a Prius, is about 2.5:1.  Gas miles in our Prius Prime produce about 2.5x as much C02 as do electric miles.).  So I decided to do a more careful and better-documented calculation.

A virtual trip to Home Depot, and a surprise.

I went to the Home Depot website and began with the first gas-powered leaf blower that showed up.  This is an ECHO gas-powered backpack leaf blower.  I downloaded the manual to see what I could find out.

My first shock was in finding that this can be fitted with air pollution controls.  For example, this model has a catalytic converter and a gasoline evaporation control system, at least in some areas.  This, apparently, is required by law, and has been required, in at least some areas, since the mid-2010s.

Source:  Manual for the ECHO backpack leaf blower referenced above.

I then looked at a similar Ryobi model, and it too has a catalytic converter as an option.  That said, the owners’ manual says that it must be replaced every 50 hours.(!)  Hard to find it labeled as catalytic, but it appears that the muffler assembly is a $50 part.  I’m guessing the average user will not bother to replace that after 50 hours of use.

Source:  Manual for the Ryobi backpack leaf blower cited above.

The important implication of this is that older comparisons — such as the 2010 testing done by Edmunds, cited above — may (or may not) be vastly out-of-date.  Those older studies predate catalytic-converter-equipped units.  It’s not clear to me whether all units are now equipped with catalytic converters, or whether the typical owner bothers to maintain those catalytic converters.  But this does make me wonder just how much all of the often-cited literature on the dirtiness of these engines is out-of-date.  I certainly see recent articles that still cite the remarkable findings of that Edmunds comparison.

It also appears that most of the advocacy articles focus on the high levels of unburned hydrocarbons.  That’s where the blue-smoke-spewing two-strokes do the worst.  All of them also seem to add in a huge amount of spilled gasoline, though how they could possibly know the average spill rate for the average consumer is beyond me.

Anyway, catalytic converters on two-stroke leaf blowers — that was news to me.  (Though if you Google it, you can find many examples.).  Maybe I’ll investigate further at some point.

For now, I’m looking for fuel consumption (which will dictate C02 output) and work produced, probably measured as cubic foot of air moved per minute.

Moving on.

After looking at a few more gas-powered leaf blowers, it’s clear that they use so little fuel that homeowners don’t care what the fuel consumption is.  The issue of fuel consumption per hour, or typical run time on a tank of gas, is simply not addressed in any of the consumer literature for these devices.

You really have to dig to get it.  Luckily, Stihl introduced some fuel-efficient models about a decade ago, and as part of that, they produced statistics on typical gasoline consumption per hour.  These were aimed at demonstrating cost savings to professional users such as landscape maintenance companies.

With that in hand, it’s just a question of comparing some off-the-shelf plug-in electric models to a couple of efficient Stihl gas models.  Here’s the calculation.

Discussion

The bottom-line figure seems completely credible to me. 

For a Prius, the equivalent number would be 2.5 to 1.  That’s my best estimate (presented in long-ago prior posts), based on our experience with a 2021 Prius Prime.

It’s no surprise that the ratio would be not quite 7 to 1 when comparing small two-stroke engines to electric motors.  In general, engine efficient drops with size, due to proportionately larger heat losses in small engines.  And two-stroke engines are designed for a good power-to-weight ratio, not for fuel efficiency.  Meanwhile, electric motor efficiency — at least at this size — varies only modestly by size.  And as a result, what was a 2.5 to 1 advantage for electric cars becomes a 7 to 1 advantage for electric leaf blowers.

That said, the global warming impact of these devices is almost negligible, at least in terms of C02 emissions.  Note, from the table above, that you’d have to run those leaf blowers for about three hours to use up one gallon of gasoline.  Compare that to the U.S. average of about 650 gallons of gasoline per licensed driver per year, and it’s obvious that leaf blowing really doesn’t much matter, in the overall U.S. carbon budget.

That said, this is just another illustration of something that I hope is becoming increasingly clear to most Americans:  The future is electric.  The rapid de-carbonization of the grid means that more and more frequently, the low-carbon option is going to be the electric option.  Whether that’s for transportation, heating with heat pumps (Post G22-058), or for moving your leaves from place to place.

On the smugness of raking, or, TANSTAAFL

I’m sure that at least some readers have thought to themselves, “Why use a leaf blower at all?  I rake my leaves, therefore I don’t use any fossil fuels to collect my leaves.”. 

Well, it just ain’t that simple. 

  • Raking consumes energy.
  • We supply that energy with fuel.
  • That fuel is a highly refined substance called “food”.
  • Food production and distribution consumes enormous amounts of fossil fuel.

One way or the other, everybody wants to think that there’s a free lunch.  In this case, the free lunch is the illusion that if you don’t consume fossil fuels directly, then you can ignore the fact that you’re consuming them indirectly.

And I’m the guy who gets to tell you that nope, there ain’t no such thing as a free lunch.  The facts are that:

  • it took a lot of fossil fuels to make your lunch, and
  • if more exercise means you eat a bigger lunch, then
  • more exercise means you consume more fossil fuels.

The only trick is that you consume those fossil fuels indirectly, via increased food consumption, not directly, by gassing up your power tools.

I was introduced to this concept in an article entitled “Bicycling Wastes Gas?“.  I can do no better than suggest that you read it.

Here’s the story of how I finally came to understand this.  In my youth, for two years, I biked to work about three times a week, during the warm weather.  Work, in this case, was downtown Washington DC.  The round-trip distance was about 32 miles.  For a guy my size, that burns about 1600 calories.

Lo and behold, I found myself eating a lot more.  Conservation of energy, and all that.  Those 1600 calories of daily exercise had to come from somewhere.  And if my weight remained stable, they had to come from an additional 1600 calories of food.

The kicker is that, for the standard American diet, it takes about 10 fossil-fuel calories to make and deliver one edible calorie.  Estimates vary, but that’s a nice round credible number.  So, while 1600 calories doesn’t sound like much energy (for comparison, a gallon of gas contains about 31,000 (kilo) calories of energy in it), once you factor in how the fossil fuel energy required for one edible calorie, suddenly, you realize that your 1600 calories of typical-American-diet embodies as much fossil fuel as … roughly half-a-gallon of gasoline.

Here’s a reference that, at the end, comes to the same conclusion that I’m about to state.  Bottom line:  As a bicyclist, eating the average American diet, I get about 63 MPG equivalent.  That is, when you divide the additional fossil fuels required, to produce the additional food I consumed, when I biked 32 miles a day, at the standard U.S. diet, by the total miles traveled, that worked out to be 63 MPGe.  (Where the “e” means that it’s compared the total fossil fuel energy to the amount of energy in a gallon of gasoline.)

(You have to be careful when you do such a calculation, because exercise calories-per-hour data are always the gross calories, including your basal metabolism.  Nobody cites the additional calories consumed by the exericise, over and above basal metabolism — the amount you would burn in any case.  You have to derive that before doing the calculation.)

Your mileage will, of course, depend on what you eat.  Potatoes embody very little fossil fuel.  Beef embodies an almost unbelievably large amount.  And many have pointed out that typical ovo-lacto-vegetarian diets embody about half as much fossil fuel as typical carnivorous diets (reference, Pimental, Cornell U.).

But to make this clear, assuming 10 fossil fuel calories per edible calorie, if my wife and I bike together, and maintain a stable weight, we actually consume more fossil fuel than if we drove together in a gas Prius.  And me, by myself, bicycling (while eating the average American diet) consumes more fossil fuel per mile than traveling on electricity in a Prius.

In other words, if I parked my electric Prius and did all my travel by bike — while eating the standard American diet — if my travel miles were held constant, I would increase my fossil fuel consumption.

Weird, huh?  And saying that inevitably makes bicycling advocates angry.  Nevertheless, it’s just math.  And a belief in basic physics, i.e., conservation of energy.

Arguably, the biggest fossil fuel savings from committing to using a bike rather than a car comes from total miles traveled.  Because, in fact, if I have to power them myself, my total miles traveled will not remain constant.  Not even when considering local transport only.  A short jaunt to the hardware store by car becomes a major investment in time and effort by bike.  Consequently, if my only option were biking, I’d be making a lot fewer trips to the hardware store.

What about leaf raking?  With that as preamble, at my weight, this calculator says I’d burn a gross total of 481 calories per hour, raking my lawn, from which I need to net out about 135 an hour for basal metabolism (e.g., just sitting and reading).  For me, then, leaf raking is a net ~350 calories per hour.  Supplying an additional 350 calories, with the average American diet, requires 3500 (kilo) calories of fossil fuel energy.  Or about as much as you’d get in 0.11 gallons of gas.  Inverting that, by raking leaves (and replacing those calories with the average American diet), I consume gasoline-equivalents at the rate of about one gallon every nine hours.

Compare that to the gallon-every-three-hours of the smaller gas-powered leaf blower above.

Conclusion:  Once you factor in the “fuel” for your leaf raking, you consume about one-third as much fossil fuel as you would using a small leaf blower.  That’s per hour.

How that stacks up per cubic yard of leaves is anybody’s guess.  But my guess is that, as with my example of bicycling above, your fossil fuel consumption from food-powered leaf raking is not hugely different from gas-powered leaf blowing.  All due to the fossil fuels embodied in the extra food required to replace the calories burned in raking.

And, as with the bicycling example above, it’s a pretty good bet that electrically-powered leaf collection — your electric leaf blower — beats hand raking, in terms of total fossil fuel impact.

There are plenty of good reasons to rake leaves by hand.  Less noise.  Great exercise.  Commune with nature.

And, as with bike-versus-car, if you are powering the operation with your own muscles, you’re probably going to do a lot less.  You’ll likely to be motivated to move the leaves less, and maybe be motivated to #leavetheleaves.  All of those are positives.

But in terms of the implications of that for fossil fuel use, that’s far from clear.  Raking requires energy.  That comes from food.  If your weight is stable, more energy output requires more food input.  And food production in the U.S. requires large amounts of fossil fuels.  Bottom line is that there ain’t no such thing as a free lunch.

Post G22-062, notes on trying to grow pawpaw from seed

 

Update, July 2023:  Near as I can tell, none of these saved seeds germinated.  So this ended up being a lot of work for nothing.  This fall, I’m going to try something easier, such as tossing whole fruit into pots of soil and seeing what comes up the next year. 

I have a couple of pawpaw trees in my back yard.  Well, two big ones, pictured above.  And then what amounts to a growing pawpaw patch all around them.

Near as I can reconstruct from old emails, these were planted in the spring of 2009, and they are:

  • Stark Brothers Mango Grafted Pawpaw.  This is a large-fruited, late-ripening variety with particularly tasty fruit.  Here’s their ad.
  • Edible Landscaping Select Pawpaw.  This is just a normal, native-to-Virginia pawpaw, that the folks at Edible Landscaping selected for better-than-average fruit.  This is a small-fruited, early-ripening variety. Here’s their ad.

I have, on occasion, eaten some of the Mango Grafted pawpaws, and they are delicious.  I no longer eat pawpaws, though — see Post G24.

Propagating pawpaws

I’ve now been asked to supply some fruit to people who want to try growing pawpaws.

I naively said, sure, I’ll just pick up some of the remains of the rotting fruit that are still on the ground.  I figured, seeds are tough, a seed is a seed.  Just pick them up, let them over-winter, and plant them next year.  Give it some time, and you too can have a delicious Mango Pawpaw.

But, as is my habit, I decided to do a little research.  And the answer is nope.  Everything I just said is incorrect.

First, from the Home Orchard Education Center, I learned one key fact:  Pawpaws do not grow true to seed.  They are like apples in that regard.  Plant a seed from a Granny Smith apple, and you’ll get an apple tree.  But it’s not going to be a Granny Smith.  Same with pawpaws, apparently.

In particular, seeds from that delicious Mango Grafted pawpaw are not going to produce Mango Grafted pawpaws.  The only way I could get more of Mango Grafted pawpaws would be to .. wait for it … graft a cutting from that tree onto some pawpaw rootstock.  Which, I now realize is probably why grafted is part of the name.  (Duh.)

Second, there’s a recommended process for saving the seeds. Apparently the seeds are fairly fragile, and require significant special treatment.  (Which, to be honest, does not quite square with the dozens and dozens of little pawpaw trees I mowed down this year.  Fragile or not, mine seem to be quite happy to sprout after falling on the ground and overwintering there.)

I’ve now started looking into what you’re supposed to do to save pawpaw seeds.  And there’s quite a bit more to it than than just picking them out of some old rotted fruit and chucking them in a paper bag until next year.

By far the most surprising recommendation is that you’re supposed to keep the seeds moist. That’s a new on on me.  Decades of growing stuff, and the advice has always been the opposite:  Keep saved seeds dry.  But for this one, nope, you have to keep it moist.  “If seeds are dried for 3 days at room temperature, the germination percentage can drop to less than 20%.” (From Peterson’s Pawpaws).

That makes any that I gathered from truly well-rotted fruit suspect.  They weren’t exactly dry, as we’ve gotten a fair bit of rain in the past few weeks.  But they aren’t guaranteed to be moist, as would be the case for seeds from intact fruit.

Separately, you have to chill them.  Commonly, they spend the winter in your fridge, inside something that will keep them moist.  I see recommendations of keeping them on damp paper towels, moist sand/peat moss mix, moist sphagnum moss, moist potting mix, or some similar sterile medium.  Inside a zip-lock bag seems to be the most common technique.

But you can also plant them outside, keep their planted area moist, and let the winter chill them for you.

Third, the common recommendation is to remove all traces of pulp and membrane from the seeds.  Apparently, there’s something in the pulp that inhibits growth.

Finally, if you plant in containers, for eventual transplanting into the ground, those containers need to be deep, as these produce a long and fragile taproot.  That much I already knew as these are reputed to be almost impossible to transplant out of the ground.  I’ll be using my paper bag technique from Post G22-012.

References also say that a) the seeds need high (75F to 85F) temperatures to germinate, one source specifies a soil temperature of 70F to 75F, b) they typically take a month to germinate in any case, C) they can do with a 24-hour warm water soak to speed germination, and d) you don’t get much foliage for the first couple of years.  All told, this seems like a project for somebody with more patience than I have.

One source — and only one source — says that wild pawpaw seeds need to be planted in soil taken from around the parent tree.  Something about microbes.  Not sure I believe that one.  That same source — and only that source — says to store them inside in a paper bag for a couple of months, then moisten and refrigerate.

References vary on whether or not you can freeze them.  Some say yes, some say absolutely not.  I am dead sure that these would freeze over the winter, naturally, so I find it hard to believe that freezing them would kill them.

Finally, the “float test” to separate viable and non-viable seeds does not appear to work on pawpaws (reference).  Which, to me, goes hand-in-hand with having to keep them moist.  This is just not a normal seed.

In any case, here are a few internet references on what you are supposed to do.

The plan

At this point, given that I want to try this, my plan is to prep a large number of seeds for overwintering in the fridge, and give away bags of prepped seeds.  If I do this again next year, I’ll know enough to collect the whole fruit before they rot, to ensure that the seeds do not dry out.

So, the plan is:

  • Start with whole fruit where possible.
  • Scrub the pulp and membrane off the seeds
  • Give the seeds the recommended soak in dilute bleach solution.
  • Bag them up in ziplock bags of moist potting soil.

Then they go into the fridge until next spring.

Edit:  Addendum

These are now done and stored away in the fridge.  All told, it took me maybe an hour and a half to process about 100 pawpaw seeds for storage over the winter.

I took the advice of several internet sites and “scrubbed” the seeds and pulp against a piece of hardware cloth, set over a bucket.  This was the most time-consuming step, mostly because I didn’t quite grasp just how hard you had to scrub, to part the seed from the surrounding membrane.  It went a lot faster once I decided to put more effort into it.  And it was obvious when I had managed to get a seed out of its membrane jacket.

I soaked the mostly-clean seeds a few minutes, then cleaned off any remaining pulp one-by-one.

Five minutes in a weak bleach solution (10-to-1 dilution of standard laundry bleach), several rinses to remove the bleach, and the seeds got tossed into Ziplock bags filled with damp potting soil.  And the bags got tossed into the back of the fridge.

The next challenge will be planting them in the spring.  As I understand it, pawpaw seedlings really don’t like to be transplanted.  They grow a long, fragile tap root before they even begin to break the surface of the soil.

Direct-sowing into the soil is preferred.   But I’m planning to raise seedlings to give away in next spring.  So I need to find or make some suitable containers.

You can find any number of very tall plant pots and containers specifically designed for growing tree seedlings.  But it is far harder to find very tall biodegradable pots, so that you can plant the seedling without disturbing the plant roots.  In particular, rumor has it that pawpaws can put out a one-foot tap root before you even see any leaves.  So I was looking for slender biodegradable pots at least one foot tall.

The best of the bunch seemed to be the lightweight Zipset (r) plant bands, 14″ x 3″ (reference).  These are more-or-less open-ended un-waxed lightweight milk cartons, and should degrade in less than a year.   They seemed to have the exact right combination of size, stiffness, and biodegradability.  They are cheap if bought in bulk, but the smallest quantity I could buy was a carton of 500.  That was far too many.

Instead, I’m going with 17″ tall biodegradable fabric grow bags (reference).  I can pick up 50 for $15.  The big unknown there is whether or not they really will degrade once planted.  I’ll bury a few this winter and dig them up before I decide whether or not to start my pawpaw seedlings in them.

In any case, at that price, the cost of the potting soil to fill them will far exceed the cost of the grow bags.  So it’s not like the bags represent a big money gamble in the overall scheme of things.  .

I decided against several varieties of home-made pots, just because I didn’t think they would be sturdy enough.  I could, in theory, make a foot-tall paper pot, out of newspaper.  Or use grocery bags, cut up and re-glued.  Maybe wrapped with jute netting, for strength. And so on and so on.

But all of those seemed to be a risk, and none of them seemed to be worth the trouble when I appear to be able to buy usable containers for 30 cents apiece.  After going to all this trouble, it didn’t seem very bright to take a gamble on the containers used to grow the seedlings.

So, tall grow bags it is.  We’ll see how this all turns out, next spring.

G22-061: Okrapocalypse, or, how does your garden slow?

Okrapocalypse

For the past month or two, when I looked out my bedroom window in the morning, I could see a half-dozen okra blossoms.  Every morning.  They are quite striking, for a vegetable flower.  They only last a day.  And for the past couple of months, my row of okra set a handful of new blossoms and seed pods daily, just like clockwork.

A few days ago, the clock stopped.  The weather finally turned a bit cooler, and I haven’t seen an okra blossom since.  Zero.  Production of new okra didn’t slow down.  It ceased overnight.

Source:  Weather underground.

Of course I knew that okra was a warm-season plant.  Everybody says that.  And the plants themselves are fine.  Just no new flowers or pods.  Our first frost date is probably at least a month away.  So maybe if we get another warm spell, that will pick right back up.

The surprise to me was how knife-edged the pod production is, as a function of temperature.  One day my okra patch was chugging right along.  The next day, everything having to do with flowers, seeds, and pods had ground to a halt.  All due to a roughly 10F drop in the average temperature.

By contrast, tomatoes and peppers are also warm-weather plants.  But they’re still putting out flowers and ripening fruit.  Albeit quite slowly, now that things are cooler.

And, of course, I’ve taken advantage of the cooler weather with a fall sowing of lettuce, spinach, and some beets.

So it’s not a total loss.  Greens are food.  Sort of.

But we do like okra in this household.  It shall be missed.

Is this mother nature’s way of telling me to get a greenhouse?

At this point, I was going to go off on a tangent about degree days, and how those can be calculated specific to individual crops.  And other such technical stuff.

But, in fact, one can just sidestep a lot of degree-day issues by growing in a greenhouse.  Why be at the mercy of the weather when you can make your own?

In fact, when you get right down to it, this early end of okra production is just another example of what I observed last spring:  It’s not very smart to provide frost protection alone, for plants (Post G22-009).  Even if plants will grow in cold spring weather, they sure don’t grow very fast.  By providing frost protection only, you go to a lot of effort to keep plants alive.  But you get very little in the way of net production, because growth is so slow.

As exemplified by the 100+ days it took my 49-day early season tomatoes to begin producing.

Not that I regret that — those early-season tomatoes produced as advertised (before the 4th of July).  They are still producing.  But I bet they would have produced earlier still if I’d had them in a greenhouse.  (N.B., tomatoes have perfect flowers (both male and female parts in the same flower), and can be pollinated just by flicking the flowers or buzzing them with an electric toothbrush.  So no bees needed.)

I have resisted getting a greenhouse, for many reasons.  Durable ones are expensive, cheap ones are just so much eventual landfill fodder.  They require that you install irrigation.  They require maintenance.  And with common plastic greenhouses, you still need frost protection, as the greenhouse itself will typically do little to warm the plants at night.

Plus, they seem like cheating, for the home gardener.  What’s the point of marking the passage of the year if you’re monkeying around with the seasons by installing a greenhouse?

That said, I already have irrigation set up (Post G22-037).  Plus, I have a roll of clear plastic that looks like a more-than-lifetime supply at this point.

And I sure wouldn’t mind getting a little more okra this year.

Not to mention the pests.  A greenhouse might keep the @#$@# deer out, so I could grow without setting up my backyard like an armed camp.

All things considered, I feel myself sliding down that slippery slope, from growing in open beds, to being the kind of backyard gardener who puts in a greenhouse.

I never thought it would end up like this.

(‿|‿)

But.

But what fraction of the slow spring and fall growth is due to temperature, and what fraction is due to reduced sunlight?   Farmers around here grow their spring crops in poly tunnels, so I know it works.  But I’d still like to know that split before proceeding.

Turns out, it’s fairly easy to get information on typical total solar energy by month.  This is from the National Renewable Energy Labs PVWatts calculator:

Doing the math, you can see that over the course of the growing season, lack of sunlight is a trivial factor at the start of the growing season, but a reasonably important one by the end of the growing season.  In October, my garden would get 30 percent less solar energy than it does at the peak of the summer.

Fair enough, that all makes sense.  Lack of sunlight isn’t an issue for early spring crops.  But for fall crops, a greenhouse might have more utility in letting existing crops fruit longer, rather than for growing new crops late in the year.

As I ponder my healthy-but-podless okra plants, I believe I’d settle for that.