If you’re among the increasing number of growers minimizing tillage on the farm, you might encounter difficulties flipping beds from one crop to the next without the aid of a plow or rototiller. Tillage can, in fact, quickly erase the mess that a previous cash crop left behind, yet minimizing tillage can provide numerous benefits to your soil. It can improve soil structure, promote water retention, add organic matter and foster the growth of microbial life.
Here are four ways you can flip beds from one crop to another without tilling up your soil.
1. Cut Out the Outgoing Crop
A simple and easy way to flip a bed from one crop to the next without tilling is simply to cut out the residue from the previous cash crop while leaving its roots in the ground. Leaving crop roots in the ground helps promote soil health by minimizing disruptions and providing additional organic matter to be broken down over time.
This technique works well for crops such as lettuce with roots that decompose relatively quickly. For lettuce, cut the heads right at the height of the soil so that the root ball doesn’t stick up too far and interfere with transplanting another crop. After that, you can simply top-dress with compost and soil amendments and rake it even one more time before planting out with another crop. The root-balls from the lettuce might interfere with a mechanical seeder, however, so transplanting another crop into the bed is probably your best bet.
You can use the same technique on crops with thicker, woodier stems such as tomatoes, peppers or kale. Although these stems take a substantial amount of time to break down, they mostly disintegrate over the course of the winter.
2. Use a Flail Mower
Another way to flip a bed from one crop to the next without defaulting to tillage is by flail-mowing the remnants of your previous crop. Whereas typical mowers chop plants down at their base and lay them down whole, a flail mower contains numerous small blades mounted on a rotating cylinder that chop the plants several times.
Although many growers use flail mowers to effectively terminate cover crops, the machines can also be used to kill cash crops that are past their harvest stage. You can use a flail mower to quickly terminate already-picked beds of greens such as arugula or baby kale. In addition to leaving the roots of the previous crop in the ground to decompose over time, flail mowing the foliage of the previous cash crop creates a thin layer of mulch that you can plant directly into and that adds additional organic matter to your bed.
You can purchase flail mowers as stand-alone pieces of machinery, or as attachments for either two-wheel or four-wheel tractors.
3. Use a Tarp
You can use silage tarps to terminate a cash crop and prepare a growing area for its next planting. The time it takes to kill off the remnants depends on the particular crop being tarped as well as climatic conditions. One to two weeks is usually sufficient. After that, you can either rake the remnants of the cash crop off the bed, flail mow it to create a mulch, or directly plant into it.
4. Top-Dress With Compost
While all the above techniques can provide effective and easy ways to terminate an existing cash crop or cover crop without tillage, none creates the (admittedly beautiful) tilth that many growers like for planting seeds. Although there is no real substitute for the tilth created by a rototiller, top-dressing a bed with compost after tarping, mowing or cutting out the previous crop can come pretty close. In addition to amending the soil and acting as a mulch, this layer of compost provides good seed to soil contact for direct seeding.