From dead hedge to mushroom nursery: growing in a brushwood wall

Dead hedges are appearing in more and more gardens, deservedly so: you stack your pruning wood between two rows of posts, the hedgehogs and wrens are delighted, and you save a trip to the tip. But one side of the dead hedge rarely gets a mention: it is the best mushroom spot you can build in a garden. Shade, shelter from wind, stored moisture and a supply of wood in one place, a fungus asks for nothing more.

Why does a dead hedge work so well for mushrooms?

A dense stack of branches makes its own climate. Low down it stays damp when everywhere else has been dry for weeks, the temperature swings more slowly than in the open, and the wind that normally dries out logs barely gets through. Those are exactly the conditions in which mycelium keeps working while it stalls elsewhere. In an ordinary border you have to hose down a mushroom log in dry summers, in the heart of a dead hedge it saves itself.

Turning a wall into a nursery

The recipe is simple: treat the dead hedge as a cupboard and the inoculated logs as shelves you slide in.

• Inoculate a few fresh logs of 50 to 100 centimetres as described in our piece on the inoculation season. For a hedge, oyster mushroom and nameko are grateful choices, and in an older wall the velvet shank does well too.
• Slide the logs in at half height, horizontally, with at least one cut end reachable so you can harvest. Not at the bottom (too wet, too much competition from everything already living there) and not on top (too dry).
• Mark your logs. A cable tie or dab of paint per species saves a lot of puzzling a year later about what sits where.
• Keep topping up the hedge with pruning wood as you always did. Fresh material on top keeps the moisture level up.

Can you inoculate the hedge itself?

Inoculating the thin branches of the wall itself achieves little: thin wood is exhausted too quickly and too unpredictable. What does work: whenever you add to the stack, slip in the occasional fresh, thicker log that you inoculated first. And the wine cap is a story of its own: scatter a layer of wood chips along the foot of the wall and mix spawn through it. The fungus gets the moist hedge foot as a gift, and the wall gets a digestion aid in return.

What belongs in the wall, and what does not?

For the growing part, the same rules apply as for free-standing logs: broadleaf yes, conifer no, and the fresher the inoculated piece, the better. The ordinary filler wood can be anything your garden produces, conifer and old dry branches included, as long as the inoculated logs do not lie directly against it. And mind the order: inoculate first, then slide into the hedge. Drilling inside a finished wall is awkward work.

When do you see results?

Expect the same timeline as free-standing logs, 6 to 18 months depending on species, with one difference: in the hedge more logs reach the finish line because they survive dry spells better. The harvest sometimes hides between the branches, so walk both sides of the wall once a week in season. Mushrooms on the shady side are often bigger and prettier than those on the sunny side.

Already have a wall lying there and wondering where the logs would fit? A photo says enough, we will point out the spot.