Mushroom Cultivation

Mushrooms are cultivated and consumed worldwide for both culinary and medicinal purposes. They are cultivated both indoors and outdoors and they are cultivated on a variety of substrates such as sawdust and agricultural by-products including coffee grounds, straw, sugar-cane bagasse, corn cobs, and many others. Mushroom cultivation can be carried out on a large, commercial scale or on a smaller scale to suit the resources of the grower.  The mushrooms that we grow at Fun Guy Farm are all ‘wood’ mushrooms – they are cultivated on hardwood logs or on sawdust-based substrates.

Small scale commercial cultivation

Outdoor

If you have access to a woodlot, and can get hardwood logs, you can add to your income by cultivating Shiitake outdoors on hardwood logs. By using our spawn and implementing proven cultivation methods for outdoor hardwood log cultivation  along with careful attention to detail you will be assured of a successful venture. The best wood species to use for commercial cultivation is Oak. Other hardwoods such as ironwood, beech, birch, hickory, alder, sugar maple and other hard maples will also produce but are less desirable for a number of reasons relating to the integrity of the bark as well as the grain and nutritional content of the wood. For example Maple tends to debark faster than Oak and thus the logs will not last as long because debarking allows the interior of the log to dry out which can kill the mycelium. Alder is softer and less dense and again, will not last as long as Oak because it will decompose and be consumed more quickly.

We supply sawdust spawn in both loose (in a bag) and plug format (sheets of 600 sawdust spawn plugs).  We do NOT supply the raw logs – these must be sourced locally in your area and they should be cut after leaf fall in the autumn and before leaf bud in the spring. The best time to cut the logs is during the winter when the bark is very tight on the log.  Take care when cutting logs in order to preserve the bark as this is critical to maintaining moisture content inside the log. Logs must rest for at least 1 month after cutting before they are inoculated with the spawn in the spring.  Limbs and logs can be left outside until spring . Stack logs in shaded area, a little off the ground, so that there is ventilation around all logs –  a ‘log cabin’ style arrangement is good and there are other patterns for stacking; stacks should be low and in a protected area to avoid wind that dries out the logs.

Indoor

An indoor cultivation operation is a much more expensive and complicated enterprise. Indoor cultivation requires a building facility with environmental controls for light, humidity, temperature and ventilation.  Suitable substrates such as sawdust and agricultural by-products are also required. Additionally the grower will need materials such as bottles, trays, racks, etc. The grower can make his/her own spawn and growing media from sterilized or pasteurized substrates or can order these from a supplier.  The costs to produce spawn are additional to the cost of the grow/cultivation facility and realize that spawn production requires specific technical expertise and equipment such as autoclaves, boilers, agar plates, and HEPA filters.

We supply spawn, inoculated blocks, and live cultures for indoor cultivation of Shiitake, Reishi, and Oysters. These must be pre-ordered – we need at least 3-4 weeks lead time on these orders.

We do NOT supply equipment.

Large scale commercial cultivation

Consultation, technology transfer, and supplies are available.  Please call Bruno Pretto directly to discuss. 416-402-9755.

 The commercial potential of an edible species for any grower depends on a number of factors including edibility and shelf life, local and regional culinary customs, the existence of a distribution network, among others. Some edible species are cultivated and consumed internationally while other edibles have not yet achieved worldwide culinary appeal and are therefore cultivated only in countries where a local market has developed. There are a few species that are cultivated strictly for their medicinal properties while a few are cultivated because they are good edibles and also have medicinal properties. The following species are currently cultivated on a commercial scale for specific marketing areas.

Mycological Information

Mushrooms are the reproductive bodies formed by certain fungi. Just like the apple on a tree, mushrooms are the “fruits” of these fungi. The actual organism that produces the mushrooms is called MYCELIUM,  a strand-like mass of white cells (also known as hyphae) found in the growing substrate which may be a dead tree stump, a live tree, or organic material in the soil.

Fungi reproduction depends on the existence of specific environmental conditions, especially the moisture or humidity level, the temperature, and the availability of nutrients including minerals and oxygen. Optimum conditions vary among species.  Under the right conditions “fruiting” occurs and the mycelium produces mushrooms.  When mature, the mushrooms release millions of spores into the environment for further propagation of the species.

 Mushrooms are classified into three types according to their specific growing characteristics.

Parasitic mushrooms attack a living host plant, usually a tree, and eventually kill it. They may also be found growing on dead trees, but they probably started growing while the tree was alive and contributed to its demise.  An example of a parasitic mushroom is the  Honey mushroom (Armillaria mellea).This type of mushroom can be cultivated but will require a living host. Some parasitic mushrooms also function as saprophytes (described below).

Mycorrhizal mushrooms form a symbiotic (mutually beneficial) relationship with the roots of trees or bushes. In fact, the root tips of all plants are coated with a fungus which breaks down the organic matter in the soil and makes it available to the plant. The plant in turn produces sugars and exchanges these with the fungus. Some of these symbiotic fungi produce mushrooms.  Examples include the Boletes, Truffles, Chanterelles, and Amanitas. Cultivation of this type of mushroom requires the other half of the symbiotic relationship which is the live tree. It is almost impossible to establish this symbiotic relationship under controlled conditions on a commercial basis. However, success has been achieved with truffles whereby a grower inoculated the roots of small oaks with the mycelium, planted them, and then waited for more than ten years before harvesting the truffles.

Saprophytic mushrooms live on dead organic matter such as dead trees, stumps, old roots, grass, straw, compost, etc. Mushrooms in this group are those that are successfully cultivated including Shiitake, Oyster, Champignons or White Button mushrooms (Agaricus spp.), Portobello,  Enokitake, Reishi, Maitake, Paddy Straw mushroom, and many others.

All of these types of mushrooms play roles in ecosystems throughout the world. One of the key roles that mushrooms play in natural systems is the decomposition of dead organic matter. Decomposition is accomplished by a succession of saprophytic fungi (the following examples are edible species but I am sure there are many other). The primary decomposers such as Shiitake, Oyster, and Wine Cap mushroom (Stropharia rugoso-annulata), start the process by breaking down the lignin and cellulose in wood, straw and other plant matter.  Secondary decomposers take over after the substrate has been partially broken down. Secondary decomposers typically grow on composted materials and include the White Button mushroom and Portobello (Agaricus spp).  Tertiary decomposers are typically soil dwellers. Some soil dwellers can be cultivated in reduced/composted substrates and these include some Agaricus species (button mushrooms and Portobello), the Orange Peel mushroom, Conocybe, Agrocybe, and some Pleurotus species.  On the other hand many of the soil dwelling mushrooms are extremely difficult to cultivate at all because they grow in nature only in association with the roots of trees and bushes and many also depend on soil organisms in order to thrive.  These latter species include morels, truffles, and chanterelles. As mentioned above these mushrooms are classified as ‘mycorrhizal’ and are not only notoriously difficult to cultivate but can take many years to establish.

Each mushroom has specific growing parameters relating to  light, moisture/humidity, temperature, availability of organic compounds and minerals as well as oxygen and/or carbon dioxide. In many cases the mushroom requires a ‘suite’ of environmental conditions which must be fulfilled for successful cultivation. These precise conditions can be quite difficult to reproduce. For example, the growth stimuli that morels require for reproduction are so complex that cultivating them indoors in controlled conditions is a hit or miss procedure at best. They can be cultivated outdoors by preparing a site suitable to their growth and  introducing the morel mycelium in form of spawn (mycelial culture grown out on grain or sawdust). On the other hand, Oyster, Shiitake, Shaggy Manes, Reishi and others depend on a less complicated interplay of stimuli in order to reproduce and have a very high success rate if instructions for cultivation are followed carefully.

Primary and secondary decomposers are the most suitable for cultivation since the mycelium of these species is usually quite vigorous and with proper cultivation techniques there is a high rate of success. In addition, substrates are readily available. The by-products from agricultural processes and the lumber industry are suitable substrates for mushroom cultivation and include hardwood logs for outdoor Shiitake cultivation, sawdust for indoor cultivation of many species, as well as grain husks and straw for Oyster cultivation.