Sunn Hemp and Cowpea as Cover Crops in Florida
Pictured here are two types of summer cover crops used by local Collier County farmer, Nick Batty of Inyoni Organic Farm; Sunn hemp and Cowpea.
image 1: sunn hemp and cowpea cover crop mix on organic farm in Collier County
Sunn hemp has been grown as a green manure crop in Southeast Asia for centuries and is cultivated in many tropical and subtropical regions around the world. In Florida, Sunn hemp is used by winter fresh market vegetable producers during the summer months. This green manure puts organic matter and nitrogen back into the soil as preparation for the next growing season.
Sunn hemp is plowed down when flower buds have formed or during the early flowering stage. Mowing and disking are common practices to incorporate plants into the soil.
Cowpea is a legume that grows well in a variety of soils. It is resistant to root-knot nematodes and has a short growing season. Cowpea can produce 3 to 5 tons per acre of biomass if managed with little or no flooding conditions.
image 2: sunn hemp and cowpea cover crop mix on organic farm in Collier County
These tested cover crops can also improve nutrient and water-holding capacities of the soil, suppress weeds and soil-born pests, like parasitic nematode which are very common here in South Florida.
For more information on cover crops benefits, varieties and management in Florida, check out these AskIFAS EDIS resources: Ask IFAS: Cover Crops (ufl.edu)