Chestnut mushroom: the golden clustered species that grows on beech and poplar

In the world of grow kits it is called chestnut mushroom, which regularly causes confusion with the brown button mushroom from the supermarket. It is a completely different mushroom. Pholiota adiposa is a clustering species with golden, sticky caps covered in brown scales, a relative of nameko, and one of the loveliest species you can see hanging from a log in autumn. We offer it as plug spawn and spawn.

How do you recognise it?

By the gold and the scales. The cap is three to eight centimetres, yellow to golden brown, glossy and sticky when moist, dotted with dark, upright scales densest at the centre. The stem is long, firm and yellow, with the same scales below a faint ring. They grow in clusters of ten to thirty from dead broadleaf wood, preferring beech, poplar and ash, often high on a standing log. The gills start pale yellow and turn rusty brown with spores. It is a striking, sunny sight in a grey autumn wood, and on an inoculated log a species you spot from a distance.

Why is it underrated?

Because it never had a culinary tradition in western Europe and most field guides dismiss it as "edible, mediocre", a verdict probably passed on old, wild specimens. Harvested young from a log it is something else entirely: a firm, nutty mushroom with a stem that stays crunchy even after frying. That is why it is farmed on a large scale in Japan and China, and why it is a fixture in the English-speaking growing world under the name chestnut. It is one of those species where growing and foraging yield two different mushrooms.

How do you grow it on a log?

Like nameko and oyster, on beech, poplar or ash, with plug spawn in February or March. Chestnut is a cool autumn species that fruits at 10 to 18 degrees, so expect the first clusters in the second autumn, usually October, and then every autumn for two to three years. It likes a standing log and moisture: burying halfway works, as does a spot in the dead hedge. If you want a cluster of this next to a cluster of nameko in autumn, inoculate two separate logs from the same beech; they want the same conditions and ripen at about the same time.

And on straw or sawdust?

Also, with spawn, which is why it is so well known in the growing world. On supplemented sawdust or pasteurised straw in a bucket or bag it colonises briskly and then fruits at cool temperatures in clusters that push out through the holes. It needs more light than oyster to get its colour; in the dark it stays pale and stretches. A cool, bright utility room in October or March is the place.

When do you harvest?

Young and closed, while the cap is still domed and the veil beneath it is still attached or just tearing. That is when the slime layer is thin, the stem crunchiest and the flavour cleanest. An opened cap with rusty gills is still edible, but softer and slimier. Cut the cluster off at the base in one go. Fresh, it keeps three to four days in paper in the fridge.

How do you eat it?

Short and hot, and the stem is the star. Sliced into a stir-fry or a bowl of noodles the stem snaps like a green bean, and the cap adds a nutty, faintly sweet flavour. Also good in soup, where the sticky layer on the cap, as with nameko, lightly thickens the broth. Do not wash, just trim the base and tear the cluster apart. Chestnut is one of the few species that keeps its bite in the freezer: blanch briefly, freeze, and in winter straight into the wok.

Who is the chestnut mushroom for?

Anyone with a beech or poplar who wants to stretch autumn with a species different from oyster. Anyone who loves Asian cooking and wants a mushroom with bite. And anyone who wants a log you can see from across the garden in October. It is not the best-known species in the range, and that is exactly the reason to try it.