Farm-Generated Fertility: Vermicomposting Horse Manure and Vegetable Wastes

2016 Annual Report for FNC15-988

Project Type: Farmer/Rancher
Funds awarded in 2015: $7,301.00
Projected End Date: 08/15/2017
Grant Recipient: Spirit of Walloon Market Garden
Region: North Central
State: Michigan
Project Coordinator:
Rachel Cross
Spirit of Walloon

Farm-Generated Fertility: Vermicomposting Horse Manure and Vegetable Wastes



This year, we essentially put our vermicompost program on hold. We kept the worms watered and minimally fed to sustain the population, but were not actively producing vermicompost or recycling farm wastes. We incorporated the original vermicompost into fresh, hot composting horse manure, and allowed the worms to move into this new compost as it cooled. As last year, we topped the pile with a thick layer of straw to overwinter the worms; as of late February, 2017, they were still alive. A sample of vermicompost was taken late February and is currently being monitored in the greenhouse for weed emergence. If clean, this compost will be used in our lean-to hoophouse and as the initial worm bed in our new system.

This project has ended up being a poor fit for our farming system. A first stage hot composting session of the horse manure is just something that we don’t have extra time for in the summer, and the uncomposted horse manure is too weed-seed heavy to produce quality compost. Transporting and chopping vegetable wastes also takes too much time, and is also ineffective unless the residues are partially dried. We’ve learned that if we want to make vermicompost, the worms need to be in a place that is visited daily and fed more tender plant materials, not manure or mature vegetable wastes.


With a project extension, we will build a three-compartment, 4’x24’ worm bed system under the northmost bench in our transplant greenhouse. We will reuse the cinder blocks from our old worm beds, purchasing a few more to finish enclosing the space in addition to materials for dividers. We will install a new, smaller mist system on a timer to keep these new beds moist. These worms will be on a diet of transplant thins and weekly trays of spent pea shoots and sunflower shoots. We are hoping that this will allow us to make clean, quality vermicompost in a space where the worms will be easily monitored and attended to. This building will take place in March, and the worms will be moved to their new home in late March/early April. Feeding will commence immediately. As each 8’ compartment fills, we will place fresh food in the compartment alongside, remove the divider, and allow the worms to travel to the fresh material. The finished compost will be scooped out, allowed to dry in the greenhouse on a tarp, and stored. We will repeat as needed, rotating among the bins.


In 2017, we will feature the vermicompost project during our annual farm tour and potluck. Our website will have a page dedicated to the trials and tribulations of this project.