KISS Plan for Vermicomposting on dairy and horse farms


To optimize ideal conditions for compost decomposition and converting compost to vermicompost (worm castings) using Red Worms, four variables should be monitored closely; temperature, moisture levels, oxygen and soil pH balance. Research conducted by experts in the industry list these variables and the ideal growth environment for Red Worms below:

• Ideal temperature: 15 to 20°C (60 to 70°F)

• Ambient moisture level: 64 to 80 percent

• Oxygen requirement: gaseous oxygen from the air.

• Soil pH: > 5 and < 9

Earthworms consume large quantities of organic material equivalent their own body weight every 24 hours. They expend energy turning the soil, which, in effect will aerate the windrows and minimize odor buildup. Half of what Red Worms eat will become viable plant food (earthworm castings).

As you become familiar with the KISS process, you’ll be an eyewitness to the methods Red Worms use to convert your compost to earthworm castings. Remember each windrow has a different time frame as to when the worm castings are ready for harvest can be processed.

Always give each windrow a little longer time before harvesting to ensure the worms have thoroughly broken down the vermicompost. Doing so will also leave more worm castings in the soil.


While your worms are hard at work for you, monitoring the amount of moisture in the air will impact their ability to work even harder. If possible, we encourage farmers to use a misting irrigation system that runs through the entire windrow.

If you have the irrigation system set on a timer, it will enable you to be consistent with watering and controlling the amount of moisture windrows receive. Remember to always keep the soil moist, but don’t over water it to where the bottom of the windrow becomes soggy.


If your windrows are in an exposed environment, it’s strongly recommended you use plastic tarps or a similar fabric to divert rainwater runoff and prevent leaching. Doing so will also preserve nutrients in the vermicompost, ensuring an optimal climate for worms.

Even after the worms have left their castings, it’s wise to cover the casting and prevent any loss of nutrients from exposure to rain or the exposed environment.

There are numerous companies you can contact which sell tarps and fabric covers specifically for composting, which can be used for vermicomposting. We recommend:

? Midwest Bio-Systems – 800-689-0714, ask for compost covers.

? Champlain Valley Compost Co. 802-425-5556, ask for the Compostex Cover.

? W.L. Gore & Associates, Inc 888 914 4673, ask for the Compoguard Cover.


Timing the harvest is critical to getting the best return on your time and investment. Worms will always create the best castings when they have an ideal environment to thrive in. Expect to harvest castings from the most active windrows in as little as two months. Depending on the size of the windrow and the environment worms grow in, it can take up to six months for castings to be ready for harvest. As you become familiar with the KISS Plan, applying it on your farm, you’ll be able to anticipate the ideal times for harvesting castings.

Learning the science of vermicomposting can be one of the wisest investments you make with your organic compost. Following the KISS plan ensures you’re following a proven process that’s used by farmers, gardeners and industry experts from around the world.

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