Perhaps the easiest mushroom to grow outside in beds is the wine cap, Stropharia rugosoannulata.
this is a tasty mushroom you’re not likely to find at the grocery store. You may hear it called king stropharia or garden giant because the caps can grow as big as dinner plates! It's a favorite of foodies and farmers alike, packing a punch with umami flavor and protein, and adapting well to sunnier sites than many other mushrooms. We've never met a more generous mushroom than the wine cap.
Description: Wine caps, or Stropharia rugosoannulata, are an incredibly robust mushroom, growing quickly on all sorts of woody debris and resilient to a range of environmental conditions. Their ability to tolerate some sun makes them uniquely suited for incorporating into vegetable gardens.
Of all the mushrooms we cultivate here at North Spore, this one most closely resembles portobellos, and is relatively easy to identify. Wine caps form a classic cap and stem mushroom and are so called for the deep burgundy color of their caps. Depending on exposure to the sun, that hue can range from a bright red, to deeper purplish hues, fading to medium brown. Caps may also feature fluffy white tufts, more common near the margins than center, especially when young. Gills are purple-gray, becoming dark purple brown when laden with spores of the same color. Their flesh and stem is cream to white and they have a ring covering their gills when young which travels down the stem as they mature. The ring is unlike the fibrous type of Amanitas, nor the cobwebby sort of Cortinarius. Instead, it's radially split which makes it prone to breaking off in chunks or appearing like a cogwheel.
Wine caps begin as unassuming mushrooms, rather modest in size. If left to grow, they can become quite massive earning the name garden giant. Seeing these specimens calls to mind fairytales and toadstools.
Ecology: Our cultivation of this species mimics their habitat preference well. As saprobes or decomposers, these fungi can be found growing on wood chips in a variety of locales. No stranger to urban or suburban spots, where mulch is used in landscaping. Though sometimes they may also emerge from gardens or lawns unexpectedly. They also appear on the forest floor in areas where trees have been cut or there's woody debris and in seasonal floodplains. They grow both scattered and in clusters. At times they fruit so prolifically they're called gregarious!
In terms of timing, wine caps are flexible and will fruit in the spring through fall in temperate climates or when temperatures range from 50-70 degrees F. The native range of wine caps spans across North America, though they're significantly more widespread East of the Great Plains.
Difficulty for Outdoor Cultivation: Beginner. One of the best mushrooms to cut your teeth with.
Our cultures: We sell four strains of Stropharia rugosoannulata. The one we use to produce our sawdust spawn was developed from a wild specimen found in Southern Coastal Maine so it's regionally adapted to our climate and hardy through winter.
Preferred Growing Methods: Wine caps thrive in a bed style of cultivating that can easily be tweaked to create mushroom mulch just about anywhere. They tolerate more sun exposure than most other mushrooms we cultivate and they're powerhouses in supporting plant and soil health. That makes them pretty perfect, in our humble opinion, for growing in gardens. If your outdoor space is limited, you can also try growing them in containers! We grew some in a fabric pot with tomatoes last year
To set up a mushroom bed, clear away debris and unwanted plants from your site. Laying down cardboard can help with weed suppression. Then, add about 2" of your substrate followed by an even crumble of your wine cap spawn. Continue alternating layer of substrate and spawn until you've used up your spawn or reached your desired bed height, 6-8" is ideal. Deeper beds may produce longer but take longer to fully myceliate before fruiting. Your top layer should be substrate, to protect the spawn from direct sun and exposure to the elements. Give your bed a thorough watering to adequately hydrate your substrate and continue watering as you would your vegetables for at least the first 4 weeks while the bed gets established. A deep water every other day should suffice. Fungi need a moist environment to grow well, but not waterlogged or soggy!
Site Selection: Wine caps will grow in a variety of environments, provided they have the right nutrition and stay hydrated. If you'd like to inoculate a full sun site, we recommend you locate your wine caps under some plants to give them a partially shady microclimate. We love growing them especially around broad leaved or bushy plants like cucurbits, big brassicas and nightshades. They're also great to add to existing mulch around perennials and trees! Find what integrates well into your environment.
Substrate: These mushrooms aren't terribly picky eaters. Most often, we grow them on wood chips or a blend of wood chips and sawdust. They prefer a mix of at least 50% hardwood if you can, the fresher the better, though they may grow on more mature substrates. Often, a local arborist or utility company is a good resource to tap for chips. Otherwise, you might be able to find aspen shavings at a pet store or undyed hardwood mulch at a farm or garden center. They'll also grow well on cereal straws and other agricultural byproducts. If you're using straw, it's helpful to chop it into 1-3" pieces.
Wood chip beds provide more sustained nutrition for more fruits over a longer period of time. Unlike indoor grows, there's no need to pasteurize or otherwise treat the substrate before inoculation. Though, soaking your substrate ahead of time to make sure it's hydrated is a great idea!
Temperature: Wine caps can be inoculated as soon as average daytime temperatures are above freezing and as late as 4 weeks before frost. They prefer to fruit in the shoulder seasons as temperatures warm or cool, between 50-70 degrees F, especially after heavy rain or spring flooding. During peak heat, growth may slow down, but will pick back up provided they stayed adequately hydrated.
Mycelium Formation: The mycelium is white to cream colored and expands in a linear pattern. It often smells rather sweet. Compared to oysters, wine caps grow slowly but steadily! As the mycelium becomes established after the first few weeks, you'll notice it takes on a thicker more rope-like form instead of the finely filamentous structure found in the spawn. We call them rhizomorphs and you'll see them attached to the base of the two mushrooms pictured here. When you're harvesting your mushrooms, save those rhizomorphic stem butts! You can use them to inoculate more substrate and keep growing.
Fruiting Information: Depending on what time of year you inoculated your wine cap and your inoculation rate, you might see fruits in the same season! Compared to growing on logs, that's a pretty quick turnaround. If you live in a temperate climate and inoculate in the spring, you may start to see fruits as early as mid-summer and into the fall. Expect to wait at least 3-6 months for your bed to fully myceliate before being ready to form mushrooms.
Once they do, you may be in for a bumper crop! Especially after a heavy rain and temperature shift, we'll see prolific clusters poking through our wood chips or straw. They easily double in size each day, so keep an eye on them to harvest before other mushroom loving creatures find them (deer, slugs, woodchucks).
Harvesting: To harvest wine cap, you can cut the stem near the base or simply twist it to free it from its mycelial anchor. Keep trimmings to spread onto cardboard or more substrate. We prefer to harvest wine caps in the button stage while the caps are still tightly curled under and close to their stem. These young mushrooms are tender and flavorful, and less likely to be buggy. Wait for the caps to become palm size and you've got a great substitute for a portobello! For best edibility, harvest before the gills become dark with spores or just before the veil completely separates from the stem.
As the wine caps continue to mature, they can grow to a gargantuan size. Large mushrooms may be milder tasting and the stems can become stringy. If you're growing for market, these are our favorite eye catching mushrooms to start conversations about. Wine caps will keep for about a week in a refrigerator, longer if they're harvested in the button stage.
Cooking: These mushrooms are well suited to a variety of cuisines and can be substituted anywhere white buttons, creminis, or portabellos are used. Just remember to cook your mushrooms! They contain chitin, a compound which also makes lobster and crab shells strong, which breaks down with heat.
Some of our favorite preparations involve grilling them, marinating them with soy sauce or coconut aminos and ginger and adding to a stir fry, or a simple saute with salt and butter. Their flavor is somewhere between a potato, asparagus, and artichoke!
Some people might experience gastrointestinal upset after eating wine caps for several consecutive days. As with any new mushroom, we advise eating just a little at first and waiting 24 hours to see how your body feels before really diving into a full meal of them.
Other fun facts: Wine caps trap parasitic nematodes in the soil and eat them as a convenient source of protein. These fungi pierce and immobilize the tiny roundworms with a specialized spiked cell called an acanthocyte. Then, they release digestive juices to break down the organism and absorb the nutrients. If grown in your garden, this carnivorous habit might help our your plants as a sort of biocontrol!
Speaking of helping out plants, wine caps decompose woody debris faster than any other mushroom we cultivate. That means they crank out organic matter to return to the soil. Soils with more organic matter have better water holding capacity, microbe diversity, tilth or structure, and bioavailable nutrients. All of these factors contribute to healthier, fuller plants.
But perhaps our favorite facet of these fungi is how easily they can be transplanted to inoculate new patches. Especially after fruiting, the fungi will go through a rest period when it's ideal to scoop up a little well myceliated substrate to transfer onto some new material or share with friends and family to #spreadthespore!
Image credit: Jacq Davis of @EpicYardFarm