The Worm Farmer’s Handbook: Mid-to-Large-Scale Vermicomposting for Farms, Businesses, Municipalities, Schools, and Institutions

Worm Farmers HandbookReview by Ben Goldberg

As an Extension Specialist and head of the Compost Learning Lab at North Carolina State University, and organizer of the annual international NC State Vermicomposting Conference, Rhonda Sherman is a dedicated and motivational voice for vermiculture and vermicomposting. Her book, The Worm Farmer’s Handbook, is the printed version of this dedication. Be prepared to go on an engaging tour of the diverse and fascinating world of worms as Rhonda shares her long-accumulated wisdom about maintaining a healthy and productive worm farm or vermicomposting operation.

As defined by its subtitle, Mid To Large Scale Vermicomposting for Farms, Businesses, Municipalities, Schools, and Institutions, the book is in-tended to be a guide to establishing a successful worm composting venture, whether for profit or ecological benefit. In no way, however, does that lessen its value to small scale worm farmers, or for those who simply maintains a bin down cellar or under the kitchen sink. As the book strongly emphasizes, there is tremendous value in gaining a practical hands-on understanding of worm composting basics before growing in scale. Drawing from her own experiences and those of others, Rhonda offers valuable tips and strategies that are appropriate to all skill levels and sizes of operation. She creates a solid platform of understanding that will help you productively manage not only your worms and system of operation, but your business management procedures as well.

Starting with a brief history and rationale for worm farming, Rhonda clarifies the terms vermiculture, vermicomposting, and vermicast, and sets a path mainly in the direction of vermicomposting enterprise. It was interesting to read that commercial scale worm farming got its start in the 1800’s when people gathered worms from farm fields to sell as bait, which led to entrepreneurial efforts such as the Shurebite Bait Company. How-to’s and guides for successfully growing worms emerged, as did a publishing company specifically for worm growers. Charles Darwin’s famous research notwithstanding, research was also done in the US on worm farming methods in the mid 1930’s, and Thomas Barrett published those discoveries in 1947 in a book entitled Harnessing the Earthworm.

(Just in case you don’t already have a copy, you can download a free pdf version here … )

Dr. Barret’s book and Earl Shields’s publishing efforts nurtured larger scale worm farming operations. Eventually the benefits of castings to agriculture be-came known and popularized, and worm farming to produce vermicompost emerged.

Rhonda’s readable science approach offers relevant information about soil chemistry, nutritional qualities, plant health, and pathogen and pest control. Charts and graphs provide useful at-a-glance references. It was interesting to learn, for example, that what worms are fed generates different qualities of vermicast, and in turn, these qualities provide specific benefits to specific plants or soils. Vermicompost can be tailored or blended with other ingredients to meet individual crop or soil needs.

Rhonda’s relaxed tour guide approach takes readers to numerous worm farms and facilities here in the US and around the world. Abundant images and sidebars provide show-and-tell examples of what others are doing in various regions and climates. It was helpful to see the pictures of the various bin and shelter designs at all the different scales of production, from the most basic to the more technologically advanced infrastructure.

It was easy to find inspiration from the interviews Rhonda had with worm farmers from around the world. It was just as helpful to review the business practices and practicalities of these producers. Whether anecdotally, or through step-by-step descriptions, the reader will receive guidance and support for every aspect of a worm composting operation, including the nuances of producing and using vermicast tea, harvesting and storing the vermicast, testing and lab analysis, troubleshooting your system, marketing your products, and so much more.

Rhonda offers a brief discussion on the use of paper products as a feed or bedding stock. While some worm farmers have settled on the use of paper, and many well informed individuals and reputable institutions support it’s use, it remains a topic of concern for me, a one-time printer. Paper and inks were once considered toxic and controversial for composting due to petroleum and heavy metals in the inks, and dioxins and other toxic residue in the paper. While it is correct to say that awareness of these concerns has been raised, and current regulations and practices limit the use of petroleum and toxins in paper and inks, they do not fully eliminate them, so a risk of exposure remains. For example, soy inks are not required to be 100% soy, nor is it practical for them to be. They qualify as such with as little as 7%, and up to 30% to be considered soy ”based”. Nor are soy inks GMO free, if that’s of interest to you. There are still other ink ingredients that control flow rate, drying time, etc. that are toxic in their own right. Printing industry regulations mentioned are for the US. If you are a worm farmer using paper in a country that does not provide similar scrutiny, then it cannot be assured that your paper will be free of toxins. Though it may be true that paper products are an available and abundant resource for your vermi-system, in my opinion, they are not risk free for toxic accumulation in the vermicompost, or for continuous exposure to workers, volunteers, or students. Please use them with whatever level of precaution you believe is necessary for your health and for the health of the users of your vermi-products.

If there is one consistent fact about composting with worms, it would be that no one ever seems to do it the same way. Within it’s great diversity of methods and perspectives, there are some common understandings and practices that will help you maintain a heathy, active, and productive system of any scale. If that is your interest, then Rhonda’s book will be a useful and highly recommended resource for your library.

Published in Winter 2018-19 issue.