Vegetable Gardening

Lettuce patch! Dig vs. No-dig; 100% compost vs. 50% compost.

Posted by Stefani Pellinen-Chavez on

I got my lettuce seeds in the ground! I wanted to run a couple of little tests today, so I made up some wheat berry meal to use as slow release fertilizer and prepped four garden squares for lettuce seeds. I spread a little coconut coir on each of the squares after prepping them to help prevent the seeds from getting lost in the soil, but other than that, each of these squares are different.

Over the summer I made an enormous heap of compost. This winter, I spread it on top of my soil to plant in. There are a couple reasons why the internet says I shouldn’t do this. 1) It’s a waste of compost. 2) Plants will fall over because the compost isn’t heavy enough to anchor them.

In my case, I have a ton of compost, so wasting it isn’t an issue. I spread this compost about 3 inches deep, so any deeply rooted plants should be able to reach the clay. Since I don’t have the experience yet to know whether this might be a disaster, I’ll be testing out mixing the soil and clay together on a couple different early crops. Today we’re testing lettuce!

a gardener holding a trowel, digging in soil with a bucket of soil and a bucket of tools.
Turning over one square foot of compost into my native clay soil.

Here’s the test:

  • Square 1, dug into the clay soil and turned the clay over into the compost at a rate of about 50/50 clay to compost, and mixed in about a cup of seed meal at the same time.
  • Square 2, 50/50 clay soil to compost, no seed meal.
  • Square 3, mixed about a cup of seed meal into the compost, did not till in soil.
  • Square 4, loosened up the compost, no other changes.
A square foot garden square with prepared soil and a purple stone marker.
Turned over with seed meal.
A square foot garden square with prepared soil and a purple stone marker.
Turned over no seed meal.
A square foot garden square with prepared soil and a purple stone marker.
Seed meal, not turned over.
A square foot garden square with prepared soil and a purple stone marker.
No seed meal, not turned over.

I don’t know what I’m expecting for the outcome here to be, but here are my guesses:

Turning the clay into the soil means that seedlings will have ready access to more minerals, and with so much compost mixed in, the soil is nice and crumbly, so there should only be upside there. Plus, because the soil is turned over to a depth of about 7 inches, vs. 3 -4 inches for the compost, roots should have an easier time digging deeper.

I don’t expect to see any immediate difference in the seedlings with the seed meal, but over time, they should grow a little greener and fuller as they gain access to those nutrients.

Stay tuned on Twitter for regular updates @decentmadam. And I’ll write up my results when I have them!