Maitake: from dancing mushroom to grow kit, and how to grow it yourself

See a grey-brown, ruffled mass at the base of an old oak in October that looks like a sitting hen, and you have found hen of the woods. Grifola frondosa, maitake in Japan, is a fairly rare forest mushroom in north-west Europe and one of the most prized edible species in Japanese cooking. We offer it as a grow kit and as plug spawn, and of all the species in the range this is the one people most often email us about with a photo and the word "wow".

How do you recognise hen of the woods?

By its shape. From one thick, branching base grow dozens to hundreds of fan-shaped caps of two to eight centimetres, grey-brown on top and white with fine pores underneath, in a dense rosette that can reach thirty centimetres or more across. In the wild it grows at the base of old oaks, sometimes beech or sweet chestnut, and returns to the same spot every autumn, often for years. It can be confused with the giant polypore, which is coarser and yellower and bruises brown; that one is less tasty but not poisonous.

Why is it called maitake?

Dancing mushroom. Until the 1970s it could only be found wild in Japan, precious and rare enough to be worth its weight in silver, and the forager who found one is said to have danced for joy. Then it was successfully grown on sawdust blocks, and today it is an ordinary supermarket mushroom in Japan. That story is told at more length in our piece on expensive mushrooms. Here it is still rare and expensive in the shops, which makes the grow kit one of the best trades in the range.

How do you grow it indoors?

Cool, humid and with patience. A maitake grow kit wants 13 to 18 degrees, high humidity and fresh air, which makes it a winter and spring species for the utility room or an unheated bedroom. It starts as a dark, almost black lump emerging from the cut that for the first few days looks nothing like food. From that lump the fronds unfold into a rosette over two to four weeks. Mist the surroundings, not the rosette itself, because water on the fronds causes brown spots. Air matters: with too much CO2 the fronds stay as thick stubs, see our piece on air and light. The instructions take you through it step by step.

How do you grow it outdoors?

On a thick oak, half buried, with the patience of someone who thinks in years. Inoculate a fresh oak log of at least twenty centimetres in spring with plug spawn, let it colonise in the shade for six months, then bury it halfway in a damp, shady spot. Hen of the woods wants contact with the soil; it fruits at the base, not the side. Expect the first rosette in the second or third autumn, and every autumn after that for five years or more. It is the longest wait of any species we sell, and the biggest harvest per flush once it gets going: a one kilo rosette from a single log is no exception.

When do you harvest?

While the fronds are still firm and the edges have not begun to dry or curl, usually when the rosette has stopped visibly growing for a couple of days. Too early wastes weight, too late and it turns tough and starts to smell. Cut the whole rosette off at the base with a sharp knife. A second flush from a grow kit is usually small; maitake puts almost everything into one go.

How do you eat it?

Hot and dry, ideally in the oven. Tear the rosette into pieces, lay them on a tray with oil and salt, and roast at 220 degrees until the edges are crisp and the centre soft. That brings out the deep, almost meaty flavour best. The pan works too, short and hot, as with oyster mushrooms. In Japan it goes into tempura, soup and rice; here it is at its best beside a piece of meat or as the meat, on a slice of bread. Fresh, three days at most; to keep longer, fry and freeze, which it takes to very well.

Who is hen of the woods for?

For the cook who wants a mushroom that impresses on a plate. For the patient gardener with a thick oak. And for anyone who has done lion's mane and oyster and is ready for the species that asks a little more and gives a little more back. Maitake is not the easiest in the range. It is the species the "wow" comes from.