Pioppino: the Italian poplar mushroom that wants to grow on every poplar

Walk through a market in northern Italy in autumn and you will see them in trays: brown caps on slender white stems, in clusters, under the name pioppino, after pioppo, the poplar. The same mushroom grows wild here on poplar stumps along ditches and roads, and nobody gives it a second look. That is a pity, because Cyclocybe aegerita is one of Europe's oldest cultivated mushrooms and, on a log, one of the most rewarding. We offer it as plug spawn, spawn and a grow kit.

How do you recognise pioppino?

By the combination of cap, stem and place. The cap is three to ten centimetres, dark brown and domed when young, paler and flat later, often slightly wrinkled and matt. The stem is white, slender and firm, with a clear ring that turns brown from spores once the cap opens. They grow in dense clusters on dead or living wood of poplar and willow, occasionally elder, at the foot of the trunk or from stumps. The smell is fresh, faintly of wine or flour. On poplar, with this combination, confusion with poisonous species is practically ruled out.

Why is this a Roman mushroom?

Because Pliny described it in the first century as a species you could coax out by wetting poplar stumps. That is, without plugs and without mycelium, exactly what we do today. It makes pioppino probably the first mushroom deliberately cultivated in Europe, long before the button mushroom. In Italy it never went away and is now farmed on sawdust; in the Low Countries it is mostly an opportunity waiting among the pollarded willows.

How do you grow it on a log?

On poplar or willow, and there are more of those here than of any other tree. A fresh log or thick branch of ten to thirty centimetres, inoculated in February or March as in our inoculation season piece, then ideally buried one third deep or laid flat on damp soil, because pioppino likes to fruit close to the ground. It is fast for a log species: the first clusters often appear in the first autumn after inoculation, especially on soft poplar wood, and then two to three times a year, spring and autumn, for three to four years. A pollarded willow or a fresh poplar stump in the garden is the perfect spot; see also where to find wood.

And indoors?

Also good, with the grow kit or with spawn on sawdust. Pioppino wants 15 to 22 degrees to fruit, slightly warmer than oyster, and plenty of light and fresh air, otherwise the stems grow long and the caps stay small, see the familiar story. From a kit the clusters come in two to three weeks, and a block gives two to three flushes. Indoors it mainly appeals to anyone wanting something other than oyster in spring.

When do you harvest?

Young, while the cap is still domed and the veil beneath it is just releasing or has just torn. That is when the stem is firmest and the cap tastiest. A day later the cap opens, drops brown spores over the cluster and the stem turns woodier. Twist or cut the whole cluster off at the base in one go.

How do you eat it?

The Italian way: in the pan with olive oil, garlic and parsley, then through pasta or over polenta. The cap is soft and mild, faintly nutty; the stem stays firm and lightly crunchy even after frying, almost al dente, and that is exactly the quality it is prized for. Use cap and stem both; nothing needs discarding with this species. It also does well in risotto and stews, and it is one of the few mushrooms that holds up in a cream sauce without going limp. Fresh, three to four days in the fridge; to keep longer, fry and freeze.

Who is pioppino for?

Anyone with a poplar, a pollarded willow or a stump of either, which in the Netherlands means almost anyone with a garden beside a ditch. Anyone who wants a log mushroom that comes faster than shiitake and tastes different from oyster. And anyone who loves Italian cooking and has never forgotten the pioppino from the market in Bologna. It grows right here.