I was so glad to find a few Burgundy capped mushrooms in my garden recently. I have been hunting for, and trying to grow this mushroom for years. Also known as the garden giant, or Stropharia rugosoannulata, this mushroom is grown in many parts of the world, and is considered by many to be a choice edible. It also has a reputation as a great companion for plants, with it's ability to break down dead plant matter, and release nutrients back to growing plants.
My first attempt to grow this species was in Canberra, on a coir substrate in a cardboard box. A friend sent me an agar petri dish culture, which they thought was Stropharia rugosoannulata, collected from near Byron Bay. I grew the mycelium on grain, then transferred some to coir, and some straight to the garden.
In the photos below, you can see the mycelium really likes coir, and grows in dirt.
After several months, I was excited to find some mushrooms popping up from the coir, which I had placed under an apple tree and covered in woodchips. In the below photos, you can see the mycelium on woodchips, and the first mushroom.
I still wasn't 100% convinced that this was Stropharia rugosoannulata, so I waited for the next specimens so I could take a spore print. To take a spore print, you need to get a fresh cap that has recently opened, snap off the stem, and place the cap on a sheet of glass, foil, or paper. If the spores are light coloured, use black paper, if the spores are dark, use white paper. So I had 2 lovely specimens under the apple tree, just about to open up. I was excited, but so were the slugs! Overnight they had eaten all the gills, which make the spores! So I couldn't be 100% sure on the ID. Then we moved to Tasmania.
Over the next few years, several mushroom hunters have sent me spores and agar petri cultures of what they believed to be Stropharia rugosoannulata, however none of them actually produced the real deal. The native version is a different species, looks different and tastes different. According to Jonathon MacGibbon from Selby Mushrooms, the native species is possibly Stropharia melanosperma. In frustration, I cleared out all my stocks of agar, grain, and semi colonised straw, and threw them into the chook pen. Chickens and ducks love grain spawn, so they happily gorged away. Two years later, I now have Stropharia rugosoannulata popping up randomly in my garden, up to 50 metres away from the chook pen! So maybe one of the many specimens I was sent was the real deal!
Identification: There is an old saying:
"there are old pickers and bold pickers, but there are no old, bold, pickers"
As with all mushrooms, get to know how to identify them correctly before eating them. Fortunately this species has few distinguishing features.
A red-burgundy capped mushroom with dark-purple to purple-grey gills
White flesh, and a stout, white stem with a bulbous base
A thick, wavy annulus (ring on the stalk) which has fine lines on the upper side.
Fruiting bodies are convex or bell-shaped caps when young, to broadly convex to flat caps when mature. The caps can be from 5 to 37 cm (2 to 15 in) in diameter, with a 2-5 cm (1-2 in) wide stalk.
The gills in young specimens start out pale when the mushrooms are immature, but as spores start to develop the color goes to purple-grey to purple-black. Gills are attached to the stem.
The spore print is dark purple-black in color, in the below picture on the right you can see the dark spores on top of the mushroom it was resting on
If you harvest one to inspect, pull it right out, and check the stem butt for thick white strands, known as rhizomorphs. These stem butts are great to use to propagate mushrooms with rhizomorphs. A simple method is to get some ridged cardboard, wet it, layer some stem butts on it, and cover with more cardboard. I put mine in a recycled plastic tub. In a few days you should see white strands, in a week there will white strands covering the cardboard. You can now transplant the myceliated cardboard directly into your garden.
There are several white forms, and a yellow form, of what appears to be a similar species, both in Australia and in America, however they are not highly regarded as edibles, and are not cultivated commercially.
Forest Fungi are happy to announce we can finally supply Stropharia rugosoannulata on agar petri dishes, as grain spawn, and on dowels.
This species needs to grow with bacteria in order to fruit. Hardwood woodchips and/or cereal straws are the preferred substrates. Simply submerge your substrate in water for a week, drain, then inoculate. Some people change the water daily, which prevents some of the foul smells that come from anaerobic composting. The submerged substrates will be hydrated, and anaerobes will have started some decomposition of the substrates. Upon draining, the anaerobes die, becoming food for the mycelium, and for aerobic bacteria which help stimulate King Stropharia to fruit.