Gardeners looking to dive into mushroom cultivation should consider growing wine cap mushrooms. They make the perfect complement to a vegetable, shrub, or flower bed and once they start growing, are effortless to take care of.
Wine cap mushrooms (Stropharia rugosoannulata), also called King Stropharia and garden giant mushrooms, are large, meaty mushrooms with red-wine-colored caps that have a deep mushroomy flavor with subtle potato and red wine notes. According to renowned mycologist Paul Stamets, wine cap mushrooms are some of the most adaptable edible mushrooms to grow, being able to be grown in outdoor beds (including garden beds) easily in temperate climates.
On this page:
Why You Should Grow Wine Cap Mushrooms
Wine cap mushrooms are not only flavorful and can adapt to different environments, they are very easy to grow in the home garden and can produce harvests for years. In fact, if you use wood chips or straw as a mulch, you already have everything you need (except the mushroom culture) to get started.
Wine caps feed on dead and decaying organic matter. As they feed on your mulch, they break it down, releasing nutrients into the soil which can then be taken up by your plants. In this way, they behave just like the fungus naturally in your garden beds now, but produce mushrooms you can eat. If you continually refresh your beds with new layers of mulch every 1-2 years, you can continue getting harvests for years. And you may end up finding Stropharia spreading to other beds over the years. A great return on investment!
Even beginners can learn how to easily identify wine caps, as they have a unique appearance, color, and size (you should never eat a mushroom you cannot identify with 100% certainty).
And speaking of eating, wine cap beds produce heavy yields of large mushrooms, around 6 to 8 inches (15 to 20 cm) tall, and occasionally producing multi-pound giants.
What You Need to Start Growing Wine Cap Mushrooms In Your Garden
The bare minimum needed to grow wine caps is a growing medium (substrate) and Stropharia rugosoannulata spawn to inoculate your substrate.
- untreated hardwood chips (1st choice)
- untreated straw (2nd choice)
- untreated hardwood sawdust
- leaf mulch or other dried plant matter used as mulch
- cold compost pile with lots of woody plant matter
Sources of S. rugosoannulata:
- grain spawn (easiest for beginners)
- inoculated wood chip or sawdust spawn (also easy for beginners)
- liquid culture syringe
- spore syringe (not recommended for beginners)
- wine cap stumps with clumps of live mycelium (mushroom “roots”)
It’s highly recommended to get grain spawn or some other inoculated spawn. Grain spawn consists of cooked, sterilized grains which have been inoculated with liquid culture or spores, which then grow into white fuzz or root-like structures called mycelium. Because grains are very easy for fungi to digest, mycelium can grow vigorously and the grains can be directly applied to your mulch.
If you know someone who is already growing wine cap mushrooms, you can “borrow” some of their wood chips or mushroom stumps to inoculate your garden beds, which was traditionally how wine caps were propagated into home gardens (whether intentional or not).
Where to Get Wine Cap (Stropharia rugosoannulata) Spawn
There are many vendors selling wine cap spawn. I would personally avoid eBay but you can sometimes find reputable sellers on Amazon or Etsy. As always, check the reviews.
Below are some suppliers of Stropharia rugosoannulata spawn:
Preparing Your Garden for Wine Caps
If you already use mulch in your garden, there is not much you need to do to get it ready for growing wine caps.
Choosing Where to Grow Your King Stropharia
King Stropharia rules best over a well-mulched bed that is somewhat shady. Whether using wood chips or straw, your mulch should be at least a few inches thick. Wine cap mycelium thrives in warm temperatures, but the ideal temperature to trigger actual mushroom formation is below around 68°F (20°C). So, shade helps in mushroom fruiting.
Because of this, the best “throne” for your King Stropharia is a perennial bed, especially with shrubs or trees to offer partial shade. However, you can inoculate wine cap spawn in any heavily mulched bed that gets shade, such as annual vegetable beds which have tall, shady vegetables (like tomatoes or corn). You can even inoculate cold compost piles with wine caps.
How to Plant Wine Cap Mushrooms with Spawn
To maximize your success of wine cap spawn establishing in your garden beds, you should inoculate your mulch in layers.
- Add at least 1 inch (2.5 cm) of mulch – untreated hardwood chips or straw – on top of the soil of your bed.
- Spread your wine cap (Stropharia rugosoannulata) spawn evenly across the mulch layer. If your wine cap spawn is in a block, you can break it up into small clumps.
- Add a layer of up to 3 inches (7.6 cm) of mulch on top of your spawn.
- Water well and evenly all over your inoculated garden bed. Water frequently for several weeks to help the mycelium establish itself.
That’s all there is to it. At this point, the wine cap mycelium will spread out like roots, looking for mulch to break down for nutrition.
Caring for Wine Cap Mushrooms
If kept in a well-mulched bed with partial shade, wine cap mushrooms require almost no maintenance. Just ensure the bed doesn’t completely dry out, but at the same time, don’t overwater, as overly soggy garden beds can drown the mycelium. Giving your wine cap bed a good sprinkle while you’re watering your garden is often more than enough.
Wine cap mushrooms do not require fertilizer. However, as wine caps digest the mulch, they will eventually require more organic matter to break down. If you add a new layer of mulch every 1-2 years, you can keep getting King Stropharia harvests for years, and it may spread to other mulched beds in your garden!
How Long Do Wine Cap Mushrooms Take to Grow
Wine cap mushrooms can take anywhere from 2 to 3 months up to 8 months to produce the first flush of mushrooms, depending on environmental conditions and how much spawn you use. After your first flush of mushrooms, you can expect the next flush to take as little as 3-4 weeks.
Stropharia mycelium grows best in warm weather (64-75°F/18-24°C) but mushroom formation is triggered by cooler (68°F/20°C) temperatures. Inoculating beds in summer can yield fall harvests, and applying spawn in spring can give you mushrooms as early as summer if it’s not too hot.
When wine cap mushrooms begin to emerge, they will appear like deep burgundy stones popping up in your mulch. These small, immature mushrooms are called primordia. At this point, they will rapidly grow to maturity within days, so check every day until you’re ready to harvest.
When and How to Harvest Wine Cap Mushrooms
Wine cap mushrooms are their optimal flavor and texture while they’re still young, up to when the cap opens up.
After the veil (the part that attaches the cap to the stalk) breaks and the cap opens up, you can still harvest and eat them but their flavor won’t be as good, and their texture will get more spongy. The rich red color will also begin to fade.
You can also eat baby wine cap mushrooms, although Stropharia are so large that even small ones are sizable and quite meaty.
To harvest wine cap mushrooms, simply pluck them out from the ground. The mushrooms are still living after you pick them, so some gardeners like to cut off the base of the stalks and toss them back into their bed so the mycelium can continue to grow. Or you can take them and inoculate more mulched beds to spread your wine caps all over your garden.
Below is a video of Paul Stamets harvesting King Stropharia in his garden and cooking them:
Shelf Life: How to Store Wine Cap Mushrooms
Wine caps should be stored the same way as other mushrooms: in the refrigerator in a paper bag or other breathable container.
Stored this way, wine caps can be kept in the fridge for up to a week. Baby wine caps can be kept a little longer. Unrefrigerated wine cap mushrooms should be eaten within a few days.
You can also dehydrate wine cap mushrooms in a food dehydrator or very low-heat oven; just cut into smaller chunks or slices to reduce dehydration time. Completely dried mushrooms kept in an air-tight container can last almost indefinitely.
Important Note on Cooking and Eating Wine Caps
Wine cap mushrooms are safe to eat, but as Paul Stamets mentions, eating wine caps more than 2-3 days in a row can lead to indigestion or nausea, especially if paired with alcohol.
Related Questions About Growing Wine Cap Mushrooms in the Garden
Where Do Wine Cap Mushrooms Grow in Nature?
Wine caps naturally grow in or along the edge of forests, where there is a lot of decaying woody plant matter and they can grow in partial shade.
Will Wine Cap Mushrooms Harm My Plants?
Wine cap mushrooms are saprotrophs, meaning they are decomposers and only break down dead plant matter. They don’t infect or harm plants, and are actually beneficial since they associate with beneficial bacteria where the mulch meets the soil, they free up nutrients as they break down mulch into rich humus, and their mycelium can kill and digest harmful nematodes.
- Stamets, Paul. Growing Gourmet and Medicinal Mushrooms. pp. 335-342.