A cropping hazel or cobnut bush ripens its nuts over roughly a fortnight from mid-to-late September, and the window is narrower than it looks: leave it too long and squirrels and jays take the lot, pick too early and the kernels are milky and shrink badly as they dry. The husk is the signal, not the calendar. Once it turns from green to papery brown at the base and a few nuts start dropping on their own, the rest are ready to come off.

Harvest and Dry Hazelnuts for Winter Storage

What you need

1 old bedsheet or groundsheet to catch dropped nuts
1 pair gardening gloves
1 bucket of water for the float test
4 net or mesh storage bags
2 flat trays for curing

Step by step

Spread the sheet under the bush and check a handful of husks. If the base has gone from green to brown and a few whole nuts are already on the ground, start picking.
10 min
Twist ripe clusters free by hand, or use secateurs on tougher stems. Leave any cluster that is still fully green for a few more days.
40 min
Gather the nuts that have dropped onto the sheet, and go back over the same ground again in a day or two, since ripening is staggered across the bush.
15 min
Wearing gloves, peel or rub away the papery husk from each nut. Most will come free easily; a stubborn husk usually means the nut inside is still under-ripe.
15 min
Drop the husked nuts into the bucket of water. Anything that floats is hollow or insect-damaged inside — discard it rather than drying it.
10 min
Spread the nuts that sank in a single layer on trays, somewhere dry and airy but out of direct sun, and leave for two to three weeks. Turn them by hand every few days so they dry evenly.
Test for dryness by shaking a nut next to your ear — a properly cured kernel rattles slightly loose inside the shell. Crack one open to check it snaps rather than bends.
10 min
Once dry, transfer the nuts into the mesh bags for storage rather than leaving them on open trays.
5 min

Afterwards

Rinse and dry the bucket and sheet before they go away for the season. Once cured, keep the nuts in their shells in the mesh bags somewhere cool and dry — they will hold for four to six months. Check the bags every few weeks and pull out any nut that has gone soft or started to smell musty before it spreads to the rest.

Questions

Can I eat them straight off the bush?

You can, but they taste milky and underdeveloped. Two to three weeks of drying firms the shell and develops the fuller flavour people expect from a stored hazelnut.

What if the squirrels get there before me?

Pick a little earlier, as soon as the husk bases start browning, and finish the ripening off the bush on trays indoors. You lose a little flavour development but keep the crop.

How long do shelled kernels keep once cracked?

A few weeks in the fridge, or up to a year in the freezer. Shell only as many as you need at a time.

Why did so many nuts float in the water test?

Usually nut weevil, which lays an egg in the developing nut and leaves the shell hollow. It is common in most years and not worth trying to salvage the empty ones.