This is just a note in another garden failure. I won’t be trying no-dig potatoes in leaf mulch again. I’m going back to planting potatoes in dirt.
Edit 2/10/2024: After seeing a near-identical failure on YouTube, by master gardener Mark Valencia (Self-Sufficient Me), I’m pretty sure that the problem was heat. Potatoes do not like heat, and excessively warm soil produces few, small, knobby potatoes. That describes his yield and my yield, despite the fact that his pests, soil, leaf mulch and potato varieties have nothing in common with mine. (I am in Virginia USA and he’s in Queensland Australia.) What we have in common is a hot climate. Too hot for potatoes at mid-summer, in both places. I’m guessing that a thin layer of dark leaf mulch, plus Virginia/Australia sunshine, allowed the tubers to get too warm. I also note in passing that Ruth Stout — the U.S. popularizer of no-dig gardening — was a New Englander.
The failure in brief
This year I tried growing no-dig potatoes using leaf mulch. Three varieties, planted with minimal effort and zero forethought, on 3/17/2023 (Post G23-016).
The russets were a near-total failure. Lucky if I managed to get back the three pounds I used as seed potatoes. But russets basically won’t grow in the South, owing to their need for a long growing season. So that was no particular test of no-dig using leaf mulch.
I dug up the rest of my potatoes this morning — reds and golds — and the results weren’t much better. I’m guessing from six pounds of potatoes planted, I might have gotten 15 pounds of potatoes back. Almost all are small. Many are misshapen. I suspect some of those are going to be unusable.
Tellingly:
- The leaf mulch had shrunk down to about 3″ in most places
- There were only two full-sized potatoes.
- Both had dug themselves into the ground.
- Several potatoes had rotted.
- Several were misshapen.
- Several had visible insect damage.
- There was considerable insect activity in the leaf mulch.
- The potatoes were as dirty as if they’d been grown in dirt, to boot.
My conclusion is that, for a lot of reasons, my local municipal leaf compost is not a good medium for growing potatoes.
By contrast, growing no-dig potatoes in straw, two years ago, worked reasonably well. Yield was less than for potatoes grown in dirt (which I think is an established fact). But I got a good lot of full-sized, good-looking, clean potatoes (see Post G21-052 for details).
If it were not for the cost of straw bales in this area, I’d go back to growing no-dig potatoes in straw. As it stands, I’ll be going back to growing potatoes in dirt. I’m not going to try leaf mulch again.
Today is St. Patrick’s day.