This year we’ve taken on the task of fully establishing our larger vegetable field in permanent beds. The goal here is to minimize the need for tillage and equipment use, while maximizing the efficient use of inputs such as manure and straw. Rather than plowing/tilling an entire field, and spreading fertilizer/inputs over the whole thing, and weeding the whole thing, we’d rather establish permanent zones of growth on which we can focus our energy and resources, leaving permanent aisles which we can ignore except to mow now and then.
We’ve also been working to establish a large block permanent of 2.5’x40′ beds that will be managed in similar manner (see foreground of above picture). However, much of this area was still pasture with thick fescue, so it needed to be plowed and tilled to destroy the sod and create the beds in the first place. Our goal was to use the equipment once to really get these set up, and then never have to use it again. With careful management and strategic mulch use, we intend not to have to till, plow, or otherwise disrupt this soil again.
In our case, we used a rotary plow, which looks like a giant drill bit. As the BCS drives forward, the rotary plow chews the soil and throws it to one side, effectively mounding it up. It works very well for trenching and/or building raised beds, which is what we used it for. By marking out the permanent bed locations, and driving the BCS in circles around that location, we continually dug out a shallow lowered aisle and built a nice raised bed. Then we put on a regular tiller and tilled the top of the bed smooth in one or two passes to make sure we’d killed and chopped up the thick fescue and other growth remaining from the pasture.
A rough result of this work is shown above. The aisles are spaced to the wheelbase of our tractor, so that we can drive over them in the future if needed and never actually compress the growing soil. As this photo was being taken, we were spreading a light cover of wood ash from our stove to buffer the pH, then working the beds into their final configuration with a hoe. These will be planted in a wide variety of summer items like beans, edamame, okra, corn, sorghum, amaranth, sunflowers, and more.
The lowest and most virgin blocks of beds are being planted in a cover crop of buckwheat and clover this year. These crops improve the soil while helping to choke out remaining weeds. Above, you see the lowest bed blocks covered in a light mulch of straw following cover crop seeding; our intention is that they grow a thick canopy of those crops that will be maintained throughout the summer before being replaced with an equally beneficial winter crop of oats and/or rye. Then we’ll be in better shape to for vegetable planting next spring.
We’re very excited about the prospects for this field of permanent beds. We’re already seeing the benefits of a similar approach in our market garden, where the weed load is noticeably down compared to 2007 and 2008 and planting/management is far more weather-independent than on a tractor-reliant field. And keeping the permanent beds means we’re only working on the soil that actually grows food, while maintaining permanent aisles that provide habitat for beneficial fauna such as toads, snakes, and good insects. This year will be a good test case for managing this field, and in 2010 we’ll really dive into using it fully.