How to Grow Mushrooms in All Seasons

1 / 2
Reishi mushrooms growing in a fallen tree log.
2 / 2
“How to Grow Mushrooms from Scratch” teaches readers how to grow a variety of edible mushrooms.

In How to Grow Mushrooms from Scratch (The Experiment, 2018) by Magdalena Wurth and Herbert Wurth, readers will find an abundance of tips for growing different varieties of edible mushrooms. Discover the best places to plant mushrooms, varieties available, and what will work best for you. Find the excerpt in Chapter 5, ““Protected” Environments for All Seasons.”

“Protected” Environments for All Seasons

Mushrooms sometimes require protection from the sun, rain, or other less than ideal weather conditions. Some mushrooms (e.g., reishi, lion’s mane, pink oyster) require more attention than others or involve specialized techniques, which suggest growing them in their own isolated, protected environment.

There are several ways to provide for such a protected environment:

  • erecting a roof over your outdoor culture(s)
  • building a mushroom greenhouse in the shade
  • a smaller, indoor greenhouse (can be a simple plastic tunnel or more complicated technical equipment)

Advantages of “protected” environments:

  • maintain high humidity
  • minimize pests
  • easier to control environmental conditions
  • protect against unfavorable weather conditions
  • rapid mushroom growth
  • increased number of mushroom flushes

Erecting a Protective Roof in the Garden

A protective roof may be of great help in grow­ing mushrooms during long periods of rain or if there is insufficient shade available in the garden. Prolonged rains soak straw cultures to such a degree that mycelial growth slows or mycelium may even die. Mushrooms  being grown in beds on the ground can also benefit from a protective roof. If the purpose of the roof is only to provide shade, a wooden frame with reed mats or an awning should do the trick.

Wooden posts can be sunk into the ground and topped with a dual-layered reed mat (from a hardware or garden store) fastened with wire or string. The shade roof should extend beyond the mushroom culture. Select a height that allows space and access for harvesting.

Wherever or whenever protection from intense rains is required, it need not be difficult to protect your mushroom cultures. The simplest method is to cover the roof with a sheet of plastic and remove it when it’s no longer needed. For a more permanent solution, you can build a more robust roof of polycarbonate twin-wall sheets. Topping with reed mats helps to maintain a more natural aesthetic.

Our Tip: When using a roof, check your cultures for moisture content more often, as they may dry out faster when protected from all rains. 

Small Indoor Greenhouses for Edible Mushrooms in Winter

There’s nothing better than cultivating your own mushrooms in the winter. Since heaters and dry air in winter do not exactly improve the grow­ing conditions for mushrooms, you will typically need to intervene during this time to ensure your cultures’ needs are being met.

A cheap and easy option would be a plastic box with a lid. You can either place your entire cut-open growing kit directly into the box as-is or remove the substrate from the bag and place it on two small pieces of wood in the box. The idea is to create a microclimate in the box with higher humidity than the rest of the room. Spray the inner walls and the substrate as needed with a spray bottle. As mushrooms need enough oxygen to fruit, do not close the container completely.

Another extremely practical possibility is an indoor greenhouse, one of the small ones used to start seeds. There are many different sizes available, so you can choose one that suits the quantities you intend to grow. Since they can also be used for their originally intended pur­pose of seed starting in the spring, the small investment may be worth it.

High-Tech Indoor Greenhouses 

Higher-tech versions of indoor greenhouses can also be useful for cultivating mushrooms. These can either consist of several gadgets linked together or purchased complete. These kinds of greenhouses are essentially made up of a large container with removable lid, a heating coil or mat with a thermostat, and a ventilator, which also regulates humidity.

In order to keep the humidity high in your greenhouse, you can cover the floor of it with moistened perlite, then place your culture on top of it. Perlite is a pH-neutral soil amender that can store large amounts of water. Further­more, it is an entirely natural product that slowly gives off its moisture into its surroundings.

Such high-tech greenhouses allow you to more or less dial up the desired temperature and humidity. This shortens the colonization phase and makes for earlier harvests.

Our Tip: This investment is especially valuable for those who wish to grow medicinal mushrooms to replace mushroom powders and teas they would otherwise purchase. 

A Mushroom House for the Garden

A mushroom house for summer months in the garden can be just as useful as an indoor greenhouse in winter. They are especially good for those mushrooms that need extra heat and humidity for their cultivation. A mushroom house is essentially a frame of some sort that is sheathed in plastic sheeting or double-walled polycarbonate sheets and can be erected in a shady spot outdoors. It should close up tightly and be easy to clean. A DIY mushroom house is great for growing mushrooms in pots, as well as for cultures growing on straw. Build it in a way that allows you to make the best possible use of every square inch (see photo above).

Our Tip: We have had excellent results bringing potted reishi logs into a mushroom house for fruit­ing. Even summer temperatures are too low for reishi where we live in Waldviertel, Austria. If this is also the case where you live, a mushroom house will be just the thing.

Special Technique: Reishi in Pots

When growing reishi on hardwood (prefera­bly beechwood), inoculate logs with the auger method. Just like for other cultures, logs are left in their full length while the culture colonizes them and, the next spring, the logs are cut in thirds. These cut logs can then be placed in pots, with cut faces cov­ered with moss. Optimal conditions for reishi mushrooms prevail in a mushroom house in summer. You can also bury logs in the ground from spring until summer, then pot them up in midsummer. Mushrooms in the mushroom house will need to be watered, as they are being protected from rain.

Once the cap has developed well and the white growth zone has all but disappeared, you can cut away mushrooms. Reishi is notable for its ability to form new fruit bodies (see photos opposite). A new mushroom emerges from the mycelium remaining in the log after the first harvest, yet the mushrooms from the second flush are just as impressive as those from the first. In winter, store logs outdoors and bring them into the mushroom house again in the following summer.

Excerpted from How to Grow Mushrooms from Scratch: A Practical Guide to Cultivating Portobellos, Shiitakes, Truffles, and Other Edible Mushrooms © Magdalena Wurth and Herbert Wurth, 2018. Reprinted by permission of the publisher, The Experiment. Available wherever books are sold.

Mother Earth Gardener
Mother Earth Gardener
Expert advice on all aspects of growing.