Post G22-037: Updates on rain barrel irrigation, parthenocarpic crops, and other projects

Posted on July 15, 2022

Above: Famous “Pickle Maze”, Hunt-Henley House, Warwickshire.

This post provides updates on:

  • Gravity-fed irrigation
  • Parthenocarpic squash and cucumbers.
  • Fusible interfacing for joining pieces of row cover.
  • Salt-free pickles

    1:  Gravity-fed irrigation system

Following a bench test of gravity-fed (rain-barrel) irrigation (Post G22-27), I have now done two real-world tests using the same 1/2″ dripline system.

Bottom line is that this works.  I may need to put a valve or two in the system to even out the watering from end to end.  But there’s no problem delivering water 150 pipe-feet from the water barrel.

First, a single 50′ length of 1/2″ dripline, run from a water barrel to a garden bed, released water at an average rate of 0.2 gallons/foot/hour.  That was measured by noting the drop in the water level of the barrel.   So this confirms the findings of my on-the-driveway test, above, using a different method to measure the water flow rate.  (This particularly dripline is rated for 1 gallon/foot/hour at 25 PSI).

Second, I hooked up my full-garden system to my water barrels, passing first through a large in-line filter.  At the very end of the system — 150 pipe-feet away from the water barrel, the flow rate was 0.11 gallons/foot/hour.  This is with 150 feet of dripline, total, attached to a “backbone” of 1/2″ distribution tubing.

That’s once again completely consistent with what I observed experimentally with a 50′ section of line.  But it means that the distant sections of the system receive water at just half the rate of the sections nearest the water barrel.

This is easily remedied by inserting a few $3 shutoff valves into the system.  That way, I can close off the driplines closest to the water barrel after five hours, and leave the distant part of the system to run for ten hours.  In both cases, as I have this set up, that will deliver about an inch of water (one-half gallon per square foot) every time I irrigate.

The more important finding is the finding of adequate flow, even at the very end of the system.  At that 0.11 gallons/foot/hour rate, I can deliver that inch of water to the very end of the system over the course of a single day.  The drip rate is visibly fast enough to deliver a significant amount of water.

The description of installing this system, in under two hours, is given in Post G22-026.

In hindsight, this has to be the best $100 I ever spent on gardening supplies.  On any given day, this irrigation system substitutes for about an hour of toting buckets of water around my back yard.  And now I know it can be run either from municipal (pressurized) water, or from rain barrels.  It’s just slower when run as a gravity-fed (rain barrel) system.


2:  Parthenocarpic summer squash and cucumbers.

Recall that I’m trying to avoid two common garden pests — squash vine borer and cucumber beetle — by growing parthenocarpic varieties in an insect-proof enclosure (Post G22-013).  These don’t need pollination to form fruit, and so I can exclude the bees (along with the pests) and still expect some sort of harvest.  This is to avoid having to apply pesticides to these plants on an ongoing basis, in order to minimize damage from these insect pests.

This seems to be working just fine.  The plants are thriving, the squash are now flowering.  So far, it’s been all male flowers, but that’s typical of squash.  I can see a few female flowers further down on the vines, so I think it’s just a matter of time before I get some produce.

The plants are a bit crowded due to the enclosure.  But to tell you the truth, so far, these protected plants look better than the ones I’ve grown out in the open air.  Maybe growing them this way isn’t such a bad idea, bugs or not.

But it’s hard to say whether or not this really is protecting them from insect pests, because neither the squash vine borer nor the cucumber beetle seems to be present in my garden this year.  I definitely saw them right on schedule, earlier this year.  But I haven’t seen them since.  I guess, absent access to their preferred plants, they’ve moved on.

For plants with a relatively short count of “days to maturity”, this makes me wonder whether I can grow a spring/summer crop under cover — as above — and a later crop out in the open.


3:  Fusible interfacing for joining pieces of row cover.

Still holding up.  So I’m declaring that a success as well (Post G22-030).


4:  No-salt pickles.

The first run at no-salt pickles merely set the stage (Post G22-033 and earlier).

This second run tries to develop a tasty recipe.  I have seven pints, with two levels of salt-substitute, two levels of citric acid, two levels of hot peppers.  Canned.  Sitting for two weeks to let the flavors mature a bit.  Taste test will occur circa August 1.

If any of them ends up worth eating, I’ll surely blog about it.