Interseeding cover crops to enhance sustainability in organic horticulture

Commodities

• Agronomic: clovers, oats
• Vegetables: cabbages, carrots, onions

Practices

• Crop Production: continuous cropping, cover crops, cropping systems, crop rotation, intercropping
• Education and Training: demonstration, extension, farmer to farmer, on-farm/ranch research, workshop
• Farm Business Management: budgets/cost and returns
• Natural Resources/Environment: biodiversity
• Pest Management: weed ecology
• Production Systems: agroecosystems, organic agriculture
• Soil Management: green manures, organic matter, soil quality/health

Cover crops can improve soil health and help manage weeds, but short growing seasons and high land prices in the Northern latitudes of the Western USA hinder their adoption. Seeding cover crops between rows of cash crops, i.e., interseeding, can assist producers with both cover crop establishment and weed management in late-season horticultural crops. Yet, there is a lack of information regarding species selection and establishment time.  

Co-developed with farmers, we propose to first conduct replicated trials at the MSU Horticultural Farm to investigate cover crop varieties and timing of interseeding in three vegetable crops to maximize their ecosystem and economic benefits while maintaining high vegetable yields and minimizing labor needs. Second, because not all farm-relevant sustainability metrics can be measured in research trials, we will interseed cover crops at three farm locations alongside our collaborating producers. At all sites, we will track the production costs, labor needs, and impacts on soil, crop yields, and weed communities to understand the impacts of interseeding cover crops on farm environmental and social sustainability. Finally, we will use this information to create an enterprise budget that will facilitate the interseeding of cover crops in the region.  

We will use our findings to co-develop with our collaborators a comprehensive education program that will include a field guide, educational video, podcast, poster, oral presentations, and journal articles. We will share these materials broadly with producers and the public alongside the Western IPM Center, Western Cover Crops Council, and the Organic Advisory and Education Council. The research will also provide opportunities for MSU students through site visits, hands-on lessons, and lab activities.  

This project will provide pioneering ecological principles and educational materials to diversify horticultural operations by interseeding cover crops, raising farm environmental, social, and economic sustainability.   

Research Objectives:

• Objective 1- Determine optimal cover crops and timings for interseeding in vegetable crops.
• Objective 2- Evaluate and demonstrate the utility of cover crop interseeding in on-farm trials.
• Objective 3- Develop enterprise budgets for production systems that include different interseeding treatments.

Educational Objectives:

• Objective 1- Co-develop hands-on training activities, guidelines, and resources to enhance farmers' adoption of interseeded cover crops in vegetable crops.
• Objective 2- Design and deliver pedagogies to enhance College students' understanding of interseeded cover crops in horticultural farms.
• Objective 3- Increase awareness among the academic community on approaches to interseed cover crops in horticultural systems.