Sunday, May 17, 2009
NO-TILL FOR REAL
Last fall we planted a cover crop of winter rye and red clover (inoculated with rhizobium bacteria for nitrogen fixation) in the lower field. We wanted to try out organic no-till to build organic content in the soil and suppress weeds while avoiding disturbing the soil food web as a result of tillage. We got a good stand through the winter. The winter before we had a large crop of winter weeds in that field, chickweed and henbit primarily. The cover crop totally suppressed the winter weeds. Great!
The technique is to cut the cover crop when it is flowering. Because they are annuals, if cut at the right time, they will not have enough reserves in their roots to re-grow during the flowering stage so they will die off. We don't want them to go to seed so we don't have new plants germinating which will compete with our crop. The cut foliage is left on the beds and paths to act as a mulch suppressing summer weeds and retaining moisture in the soil. Since there is no tilling, weed seeds are not brought to the surface to germinate. The roots are broken down by the organisms in the soil food web to provide nutrients for the crop.
We will wait a couple of weeks to see if we cut at the right time to avoid re-growth. If not the worst that can happen is that we'll have to cut it again. We hope to plant corn and beans through the mulch really soon.
It looks like this could work!