Integrating Grass-Clover Systems for Weed Management in Vegetable Production: Rotation and Alley Strategies

Commodities

Practices

Weed pressure significantly reduces vegetable production efficiency across Missouri. Three smallholder vegetable farmers face persistent weed problems including annuals such as pigweeds (Amaranthus spp.) and giant ragweed (Ambrosia trifida) to aggressive perennials like Carolina horsenettle (Solanum carolinense). Current management relies heavily on hand weeding and herbicides, increasing costs and limiting organic market opportunities. Missouri smallholder farmers seek sustainable alternatives using competitive plant systems to suppress weeds while maintaining vegetable production. This two-year partnership will test whether orchardgrass-white clover or perennial ryegrass-white clover cover crop mix provides superior weed suppression in vegetable production systems. Both grasses are readily available, but farmers lack on-farm data comparing their effectiveness. The project will evaluate both systems using complementary strategies: rotations on heavily infested field sections to rehabilitate problem areas, and permanent alley strips between vegetable beds to suppress pathway weeds. This approach will comprehensively address sustainability components in terms of being economically viable (25-40% reduction in hand weeding labor, decreased herbicide costs), environmentally sound (reduced chemical inputs, nitrogen fixation, enhanced biodiversity), and socially responsible (farmer-driven solutions). Findings will be disseminated through on-farm visits, field days, and extension publications, which will provide practical weed management recommendations for vegetable producers across the North Central region.

The long-term goal of this project is to provide vegetable farmers with data-driven recommendations for integrating competitive grass-clover systems that reduce reliance on hand weeding and herbicides while maintaining productivity. Specifically, we will:

1. Compare weed suppression between orchardgrass-white clover and perennial ryegrass-white clover on three independent vegetable farms
2. Evaluate rotation strategy (severely infested areas) and alley strategy (active production areas) for practical integration
3. Measure weed density and sod establishment across varying weed pressures, including deep-rooted perennials
4. Assess strategic mowing as complementary management for challenging perennial weeds
5. Disseminate results through field days, workshops, and extension publications