The use of tillage is widespread in organic vegetable production, due to its importance for cover crop incorporation, seedbed preparation, and weed control. However, its harmful effects on soil health have spurred interest in systems that reduce the need for tillage. Because nitrogen is often limiting under high residue/reduced tillage conditions, fertilizer management is considered key to crop productivity.
Sustainable production of summer squash involves multiple management practices. Some cover crops can be “rolled” when mature to produce a ground-covering mat. The cash crop is then planted in tilled strips made in the residue. This “strip-tillage” technique provides a weed-controlling, moisture-retaining mat that is biodegradable, unlike plastic mulches. The reduction in tillage can improve soil health. Row covers provide a favorable microclimate and act as a physical barrier to pests when placed over young transplants.
At the 2012 Fruit and Vegetable Field Day held at the Iowa State University Horticulture Farm, Ames, Iowa, one of the major challenges highlighted by commercial vegetable growers was “weed management.” Growers called for research on sustainable and environmentally conscious (less herbicide) ways of weed management. Use of cover crops to suppress weeds was one of the outcomes of the discussion. The goal of this project was to evaluate and study what advantages exist under Iowa growing conditions for four cover crops to satisfy farmer’s goals.