by Greg Marley
We live with the mystery of mushrooms appearing fully developed in our lawns and gardens seemingly overnight. How can it be that they come from nowhere so rapidly? Indeed, there are a number of smaller fragile mushrooms, such as the strikingly beautiful Coprinus plicatilis, the parasol inky cap, that appear fully formed on our lawns and paths early in the morning only to dry out and wither in the afternoon sun. This rapid growth is due in part to the fact that, in the mushroom button stage, all the cells of the mature mushroom are already present in a tightly compact state. The high-speed growth happens through water uptake rapidly filling out these compacted cells. Within a very few hours, in some species, the button, which has been forming quietly out of sight for several days, expands into maturity and begins to release its crop of spores into the air. In reality, most fleshy mushroom require several days to reach maturity and will continue to mature and release spores for a number of days if the weather conditions remain moist. Others can remain active for weeks, and some woody polypores for several months.
What does the permaculture mushroom gardener need to take from this fungus life cycle primer? The mushroom species available for cultivating in our gardens are saprobes, and require a source of dead plant material as a food source. Fungi are somewhat clumsy in the uptake of the nutrients they absorb from the environment around their hyphae, and some of these nutrients become immediately available to the roots of plants growing nearby. Later, as the fungi die, they release even more nutrients back into the environment. The decomposition of plant tissue and recycling of nutrients happens constantly in the organic layers of healthy soil and forms the basis for the fertility of topsoil. Cultivation or encouraging mushrooms to grow in an integrated garden is a process in which the growing fungus releases the nutrients bound up in dead organic matter and makes them available to your garden plants. This breakdown of organic matter also builds the fertility and structure of the soil. A byproduct of all this soil-building activity is the crop of mushrooms you bought the sauté pan to cook.
2. Evaluate your property for good mushroom cultivation sites.
Mushrooms are made up of 85–90 percent water and their mycelium is equally high in water. They grow best in habitats with consistent moisture, protected from the drying effects of sun and wind. Most suburban and rural yards are a mixture of microhabitats created by variations in sun exposure, soil texture, existing plantings, and moisture content. It is important to choose a site on your property that makes it easy for your mushroom bed or logs to stay damp. Here is a list of considerations:
• The north and east sides of a house are normally the most fungal friendly because they see the least sun.
• An ideal site has partial to full shade and minimal wind exposure. These conditions are best formed by a mix of trees and shrubs forming an overstory canopy and a windscreen.
• For mushrooms growing in wood mulch, compost, or planted directly into soil, it is important that the soil drains. Though moisture is vital, sitting in standing water for any period of time will smother the fungus. If you have heavy, wet, clay soil, consider a raised bed.
• Though a mushroom planting will benefit from protective shade, a mushroom bed among crowded trees and shrubs might find itself robbed of moisture by thirsty roots. This happened to me when I put a bed of garden Stropharia along the edge of a dense old lilac clump with two nearby trees. The crowded roots drank up the moisture, leaving my Stropharia too dry to grow.
Most of the above list is derived from my own trial and error as well as suggestions from a number of general sources.
3. Consider available sources of food for hungry fungi.
If you want to grow mushrooms in the garden, you need a “substrate,” a usable source of dead plant material to serve as a food source for the growing fungi mycelium. Any experienced gardener knows that applying a thick layer of wood mulch to the garden helps to retain soil moisture by reducing evaporation from the soil surface and also stops weed seeds from germinating. The fresh raw wood also tends to rob nutrients from the soil in the short term as the nutrients are utilized by the fungi and slime molds to begin the process of rotting the wood fibers. Over time, the nutrients will become available as the mulch is reduced to soil. Mulch, properly chosen and used in a garden protected from both direct sun and complete inundation by water, can be used as a food source for a number of fungi. Other fungal food sources useful in outdoor home mushroom cultivation might include:
• Stumps of trees, both hardwood or conifer, left in place
• Recently cut lengths of wood (logs)
• Straw, hay, or other agricultural waste
• Shredded cardboard or paper
• Cotton cloth or old clothing, made of other natural fibers (avoid silk)
• Composted leaf piles or composts of mixed yard waste
Look around your yard, neighborhood, and town for any likely source of uncontaminated plant waste and consider its potential to make mushroom mycelium happy and you may have a substrate for home cultivation. Remember, this is an opportunity to reuse or recycle plant waste that, in the past, you may have paid to be carted off to a landfill. Some substrates to avoid include branches or logs that have been dead for more than several months (less time if cut during the warm or dry time of the year). Also avoid composted wood mulch, as it is already colonized by fungi and less likely to be a welcoming home for new species. Also avoid mulch that is made up of only bark. Avoid any paper, cardboard, or plant material that might be contaminated with chemicals or pesticides and definitely avoid any contaminated with fungicides.
4. Ensure that you have access to water.
There will be times when nature will not deliver the moisture needed by your mushroom crop on the schedule the fungus needs. Ask any farmer or gardener; nature cooperates when it pleases her. Since the single most crucial environmental need for mushroom cultivation is water in adequate amounts delivered at reasonable intervals, a handy source of water and a garden hose are almost essential. The drier and more unpredictable your growing environment is, the more important it will be to have a back-up water source. A sprinkler or spray is generally ideal, though for log cultivation, especially for shiitake mushrooms, the ability to soak your logs in water to trigger fruiting is important. A thirty-gallon plastic trash receptacle works very well for a small number of logs.
5. Cultivate patience and active observation.
We live in an age that tends to encourage the belief that events unfold magically, without effort and planning. Our media images and sound bites are filled with meals instantly appearing out of microwaves, homes being cleaned with a wave of the hand, and children marching directly to bed with clean faces and homework finished while we complete our graduate programs online in our spare time. Mushrooms do not watch TV, and don’t have cable or Internet access; they are fickle, earth-based living creatures with specific living requirements and their own internalized clocks. When we cultivate mushrooms, we seek to carefully set up a living situation that will make them happy enough to give us their offspring for dinner. That takes time and requires that we stay aware of the needs of our wards and respond, as needed, to make their lives easy. Just as growing a backyard vegetable garden requires that we learn the skills and techniques to make the vegetable plants happy, growing mushrooms requires us to build similar skills. The difference is that we have been cultivating plants for many centuries and can peer back on a long line of ancestors whose lives depended on the skills of plant cultivation. We have a complex, established civilization today due, in part, to their success in making plants grow. Man is a beginner at growing mushrooms, and very few of us can rely on the teachings of past generations of relatives to pass on the skills.
The Russians refer to mushroom picking as the quiet hunt. There is no noise of guns, drama of blood, or death throes; it is a time of being at one with the forest. I see growing mushrooms as quiet farming.
Cultivating mushrooms requires that you learn about the growing needs of fungi and
how to create a suitable environment. Then it requires that you monitor your crop as it develops in order to continue to supply those needs over time. At the very least, and in ideal conditions, it takes three to four months in a temperate climate for the first crop of mushrooms to appear. Commonly, you will wait six months or even a full year before you see your first mushroom from a log or bed you planted the previous spring. Just as a tomato patch needs soil preparation, seed planting, watering, weeding, thinning, pinching off leaders, staking, weeding, watering, fertilizing, and vigilant watchfulness for pests, so will a mushroom patch benefit from regular care and feeding. As the mycelium of the fungus is colonizing the sawdust, log, or compost as it grows, it is not nearly as visible and encouraging as watching the tomato vines grow larger and bushier, flower, and develop green fruit. Fungi grow out of sight, hidden beneath the bark of the log or under the covering top layer of straw, soil, or wood chips. There is little visible sign or encouragement before, magically, just like TV, the developing mushrooms appear on the surface and almost leap into your basket. The quiet farming is the long interval between bed preparation and planting and the eventual sign of fruit. It is during this interval that active patience is most needed to ensure that the fungi maintain moisture. Look for signs of drying by poking beneath the top layers in a mushroom bed or observing signs of checking on the cut end of a log in which the fungus is growing.
Getting Started with Home Mushroom Cultivation
Want to grow your own mushrooms? Start small and start easy. Just as you wouldn’t start your six-year-old out on a unicycle, choosing instead a tricycle or a bike with training wheels, begin growing those mushrooms that are easy and generally give encouraging results. Many mushroom companies offer products that only require you to provide a microclimate to encourage fruiting. They send you a block of sawdust or other suitable substrate mix that is fully colonized with the mycelium of your choice of mushroom and ready to fruit in the appropriately moist setting. The most popular species include varieties of shiitake and oyster mushrooms, though there are other species to choose from that are edible, medicinal, or both. Fungi Perfecti of Olympia, Washington (www.fungiperfecti.com) has been offering such kits for many years and stands behind their products.
Some mushroom companies, such as Field and Forest Products out of Pestigo, Wisconsin (www.fieldforest.net) offer kits that include all the material you need to grow mushrooms on an unused roll of toilet paper or paper towels (a ready source of cellulose). The kits include the spawn (mushroom mycelia grown out on sawdust), special breathable bags to create a microclimate, and complete instructions. Both of the companies above and others offer a wide range of mushrooms for the home or commercial grower and the cultivation products and support needed to increase the likelihood of success. Few companies will guarantee success—that is up to you.
An advantage of indoor cultivation is the ability to control temperature, moisture, and air circulation more easily. Starting indoors also helps fill in the learning curve in a manner that is somewhat independent of seasons. As long as you set it up thoughtfully, you can create the right temperature and humidity needed for your indoor patch in any season of the year.
If you decide to pursue outdoor cultivation, it is vital to plan your mushroom cultivation to match your location and climate; your macrohabitat. The species and varieties of mushrooms that grow well in Georgia and South Carolina will generally struggle in the harsher winters and cool springs of northern New England. Today we benefit from several decades of careful strain selection of the commonly cultivated mushrooms and you can purchase strains suitable for cultivation in a range of temperatures. Shiitake mushroom strains available from a number of companies have been selected for the broadest climate ranges. Whether you grow shiitake in Maine, Georgia, California, or Michigan, you can choose strains to match your climate and choose them to start fruiting in the cool late spring and, with strains that fruit in warmer temperatures, extend the availability of your harvest into the warm days of summer. The same is true with oyster mushrooms, though it is often accomplished with differing species. Some species have evolved in tropical climates and others, like the almost ubiquitous Pleurotus ostreatus, will fruit in a variety of conditions and climates and thrive in the northern United States. Most reputable companies will provide the information needed to choose appropriate varieties; a small list accompanies this text along with additional sources of information (see the Appendix).
Depending on the vagaries of your particular climate, outdoor cultivation is best begun in the non-winter months. For much of the United States, with our temperate climate, most mushrooms are best started outdoors in the spring to early summer or in late summer to fall. The climates of the Deep South, Southwest, and West Coast will each require manipulation of the timing of planting to optimize success in those regions. For log cultivation, the ideal is to cut the trees in the end of winter and to plant the spawn into the logs in the first warm days of late spring. A live tree has some built-in defenses against fungal invasion, and waiting a short time after cutting allows for easier invasion by your chosen mushroom. There is a balance, though; if you leave the cut logs around very long, you allow other species of fungi to attack the new tasty wood and these invaders will compete with your crop.
The Easiest Mushrooms to Grow at Home
Wine Cap Stropharia
The wine cap Stropharia or garden giant, Stropharia rugosoannulata, has not been a well-known edible in the United States until recently. This is a wild species that has become increasingly common due to our use of wood mulch as a landscape element. It is an aggressive and voracious wood rotter in a moist bed of wood chips and soil, and fruits prolifically, if not predictably. Grow these in a bed of mixed hardwood chips and sawdust, or on the mulch for your raspberries. If you use wood chips to make paths through your garden or woods, inoculate your path with Stropharia and enjoy collecting your dinner from the edge of the path. This mushroom is best planted in late spring or early fall with crops in spring and late summer to fall beginning the following season. I also have grown these in my potato beds by hilling up the spuds with a mixture of soil and wood mulch inoculated with wine caps. The base of each mushroom usually has thick threads of mycelium attached. Use the cut bases of wild mushrooms as a means to plant this species into your garden mulch bed. This beautiful mushroom with burgundy cap and deep gray gills is best picked and eaten before the cap fully expands. Commercial spawn is available from several sources to get wine caps started in your mulch bed.
Oyster Mushrooms
Oyster mushrooms (genus Pleurotus) come in a number of different species and a bewildering array of varieties and cutivars suitable for a wide range of growing conditions. Depending on your climactic needs and personal proclivities, there are oysters that will grow from Puerto Rico to Alaska and all stops between. You can find oysters that produce white, gray, blue, yellow, or pink mushrooms, and species that fruit in the summer’s swelter or only after the first frost of autumn. They are assertive, forgiving growers and can consume and fruit on a bewildering array of organic food sources, from logs and wood chips to straw, paper waste, coffee grounds, newspaper, banana leaves, cotton waste. . . . The list of substrates used successfully worldwide would fill this page and overflow your imagination. For the beginner urban, suburban, or rural American, start out using logs of soft hardwoods (poplar, alder, soft maple, and such), straw, wood chips, or sawdust.
Shiitake
Shiitakes are the button mushroom of Japan and China. For the past century, this species was the dominant cultivated mushroom in Asia and remains a stalwart in those regions of Asia where mushroom cultivation innovation has reigned supreme for many years. Historically grown on logs of the shi tree in Japan, log cultivation remains the easiest method for the home cultivator in the United States. The shi tree is a member of the oak family and shiitake grow best on oak logs, though success has been high on several other tree species. A cut section of a recently dead tree with bark intact
is an excellent incubation chamber, protecting the growing mycelium from the drying effect of sun and wind and the attack of bacteria, molds, and insects. Shiitake mycelium is sold as spawn colonizing small wooden dowels. These are “planted” into the log via a series of spaced holes bored into the fresh log, filled with the wood dowels and then sealed over with wax to protect the new site from drying. The inoculated logs are stacked in the shade and monitored for adequate moisture for at least six months to give the mycelium the time needed to colonize the log. The home cultivator can choose from a number of shiitake varieties suited to grow in a wide range of climates. Some trigger mushroom fruiting at low temperatures and others will fruit in warmer weather. This allows the grower to have several strains of mushrooms that will extend the time of fruiting for a longer supply of fresh shiitake. The colonized logs can be “shocked” into fruiting by soaking them in water overnight or jarring them with a rubber mallet. The inoculated logs will continue to produce crops of mushrooms seasonally for several years with the longest productivity coming from logs with the greatest diameter.
A number of other mushrooms are readily available for home cultivation. Again, I recommend cutting your teeth with the easy ones and progressing to more challenging mushrooms as your skill level matches the challenge. Mushroom cultivation requires learning, time, and some attention to details. Beyond that, any twelve-year-old can do the work. Then you can motivate the pre-adolescent to learn cooking skills to use with his or her first crop!
