Updated: Jan 16
An update on our experiment
Our sunn hemp summer cover crops are fascinating stuff. As you may know, Jennifer and others decided to try sunn hemp as a cover crop because it produces significant quantities of biomass and nitrogen in a short period of time. Sunn hemp also supresses vegetable-damaging root knot nematodes.
The key as the sunn hemp grows is NOT to let the plants flower or go to seed. So, we cut the taller sunn hemp plants in half and lay the stems on the ground next to the ones that are shorter.
Chop and Drop
About four weeks before we plant our fall garden, we’ll cut all of the plants at the ground level, leaving the roots in the soil. It’s fine to leave all of the biomass in the garden bed, but the stems do not decompose as quickly as the leaves, and it might drive you nuts waiting for the stems to break down. So, if you are a patient soul, lay the stems on the ground as "green mulch." Over time they will break down and feed your soil. If you’re less Zen-leaning, you can strip off the leaves and lay them in your garden bed to decompose, then chop the stems into small bits and put them either on your bed to decompose or in VISTA's compost bins.
Interested in learning more about sunn hemp? This report gives an in-depth, technical look at growing sunn hemp.