Marina D’Abreau Denny, Extension Associate
photo by University of Cincinatti
Of all the enterprise opportunities for private landowners, mushroom growing has the potential for the fastest return with the lowest financial investment and minimal space needed. Specialty mushrooms typically sell at wholesale prices of $3 to $6 per pound.
Several specialty type mushrooms are grown and sold in the United States, including oyster, shiitake, maitake, and lion's mane. Shiitake and oyster mushrooms are the best choice for small-scale production, since they don't require a lot of equipment and space.
Shiitake mushrooms are often sold in grocery stores, health food stores, and farmers' markets and are also quite popular for their flavor and consistency. Oyster mushrooms are easy to grow and can be harvested in as little as 6 weeks.
photo by Alabama A&M University
Probably the easiest substrate on which to grow either shiitake or oyster mushrooms are small-diameter hardwood logs. The disadvantage to growing on logs is that the mushrooms will only be available for harvest seasonally. Other growing media, like sawdust or hay, can provide a year-round supply of mushrooms.
Shiitake mushrooms can grow on 3-foot long logs, and a single log may bear up to five crops of mushrooms. While oak is the preferred species, but beech, chestnut and other hardwoods work just as well.
During cold months, greenhouses and converted farm buildings can be used for mushroom production. If you plan on doing outdoor production (ideal for spring and fall), the logs need to be inoculated with spawn (a starter mix of fungal mycelium and sawdust or grain), covered with shade cloth, and set aside to allow the fungi to develop. Spawn can take anywhere from 6 to 18 months to develop, depending on the log species, diameter, moisture, and temperature. At the end of this development period, transfer the logs to a cool, moist area where the mushrooms can grow and be harvested.
Oyster mushrooms are also best when grown on hardwood logs, but many growers will opt for artificial substrates, such as composted straw, chopped wheat straw with cottonseed hulls, and sawdust, which is then placed in sealed plastic bags, bottles, trays, or beds in a controlled environment after sterilization and the addition of spawn. In about 100 ft2 of growing area, you can produce as much as 2,500 pounds of mushrooms a year. Even selling at the low-end wholesale price of $3 a pound, that's a potential of gross revenues of $7,500 a year, before subtracting production, management, and labor costs. An added benefit of oyster mushrooms is that they freeze or dry quite well, so if you can't sell your entire harvest right away, freezing or drying enables you to sell your oyster mushrooms days or months in the future.
It's important that you understand not only the ins and outs of mushroom growing, but marketing strategies to make the most of your product. A starting list of things to consider includes:
Many commercially available mushrooms are rich in proteins, vitamins, and minerals and are low-fat. There are also claims that certain species have the potential to fight cancer and viruses and reduce cholesterol and the risk of heart disease.
However, use caution when choosing which type of mushroom to grow or when deciding how to market your mushrooms. Hard-core, scientific evidence for their use as a "miracle food" is often sketchy, at best. Don't use unsupported health claims in your marketing to avoid being accused of false advertising. Make sure that you are fully aware of all local, state, and federal laws regarding production and marketing of food products, and meet or exceed them.
If your mushroom business grows to the point that you need to hire outside employees, be sure that you provide the appropriate safety equipment, such as masks or respirators, to protect them from fungal spores. Oyster mushrooms, for example, produce spores that may cause allergic reactions in some people.
There is also the potential risk of being sued by a consumer who becomes ill and claims that you sold them contaminated produce. Reduce your liability risks by
Whether you choose to grow your mushrooms indoors or out, you'll need to control for pests and diseases. Even minor temperature or climate fluctuations can reduce yields or spur the growth of "weed molds" which can decay the wood on which the mushrooms are growing. Insects, such as termites, bark beetles and springtails, and wildlife, including slugs, snails, birds, squirrels, and deer, can become serious pests for mushroom farmers, especially with outdoor operations.
Indoors, you'll need a certain degree of technical expertise to operate and maintain proper environmental controls. Growing facilities must be kept clean to avoid introduction of potentially toxic contaminants. Pests like fungus gnats can be a common problem and need to be managed appropriately.
If you're not comfortable meeting with people and "selling your wares," then this part of the process will be the most difficult. Your primary outlets to which to sell your mushrooms will be restaurants, farmers' markets, and grocery stores.
Visit local restaurants and offer free samples (along with a potential recipe or two) to the chefs. The prospect of promoting dishes made with locally-grown produce can be quite appealing. Be sure to ask a lot of questions of your potential customers, including:
Most customers at farmers' markets are looking for quality foods from local growers, so you're liable to sell quite a bit in a weekend. Research the space availability and vendor rules of the farmers' markets in your area, and determine the benefits of selling at several over a wider geographic range, or just one or two nearby.
Grocery stores will often purchase their mushrooms from out-of-state distributors. Speak to the manager of your local store to determine if your product has a chance of being sold there. Stress the fact that most mushrooms taste better when fresh picked, which is an advantage of your product over those shipped in from elsewhere.