For Grow Biointensive, the system of growing that I’m using, it’s critical that I use ~60% of my growing space to grow grains such as Wheat, Sorghum, and Corn. The short version of the story is that grains are a fabulous way to build and ensure lasting soil fertility.
But here’s the thing: the Grow Biointensive folks are a lot more energetic than I am, and they put in the time to grow their own grain seedlings, and then transplant them one by one into garden beds, with optimal spacing. On the one hand, their garden beds look beautiful and they get optimal yields. On the other hand, based on calcs I did for a theoretical garden and diet plan, for a garden for two people I’d be planting about 15,000 grain seedlings every year. It’s daunting.
So this year I decided to make yet another attempt at direct seeding of grains. I tried half-heartedly last year, and I got crummy results. The reality is that getting strong germination requires technique, and I wasn’t applying much. “Just chop in the seeds and keep them well watered,” was what I heard. Yeah right.
But this year, after spending too much time transplanting Cereal Rye seedlings, I said “no mas” and put in a real effort to get direct seeding of grains to work. Here’s what got me results:
1. Good soil prep is critical. Before seeding, I removed the previous crop, weeded, did a single dig (deciding that a double dig wasn’t necessary this year), and then worked my compost and amendments in. In my experience, this is a big part of the labor it takes to actually plant. Putting seedling or seed in the ground can seem easy after all of the prep.
2. Protecting the prepared soil is critical. Once the soil was prepared, I watered it well and then covered it. Burlap is best, but regular black landscape/weed fabric is fine. Just try not to leave it uncovered. And keep watering it through the cloth, since the soil is very much alive and needs the water.
3. Pre-soak your grain seeds. I had heard about doing this, but now I realize how critical it is. It helps tremendously to get the seeds into the “blast off” phase of germination. And since your soil is already prepared and well watered, it has a good home waiting for it. I soaked my grain seeds for about 12 hours, but my sense is that you could even soak for a day or two. I found a Wheat Emergence study that looked at length of soaking, and planting depth. 12 hours (the longest they tried) and 3″ (the deepest they tried) was the best.
4. Plant your seeds deep enough. I have often been worried that if I planted my seeds too deep, they wouldn’t come up. There is often repeated conventional wisdom about burying seeds no more than twice the depth of the size of the seed. However in my experience it really depends on the seed. And indeed, when I took the advice of the study and planted my Cereal Rye 3″ deep, it did really well. In fact my direct-planted Cereal Rye is growing much better than my transplanted Cereal Rye.
5. Keep the soil covered until seedling emergence. The biggest enemy of germinating seeds is lack of moisture. You have to keep them well watered, but if you don’t live next door to your garden, or even if you just get a very sunny day, this can be tricky. Fortunately, pretty much all vegetable and grain seeds *do not* need light in order to germinate. Thus after planting the seeds, we can cover the soil with burlap to keep the soil as moist as possible during this critical time.
6. Keep the grain seedlings shaded until they are tall and strong. Even after emergence, moisture can be a real issue for new seedlings. I think that moisture is a bigger issue than sunlight at this point, and so I’m willing to trade off 30% of the sun power for dramatically better moisture retention in the soil. It’s a matter of judgement as to when to remove the shade cloth.