Why collect your own meadow seed

Late summer is the most generous time in a wildflower meadow. By August the ox-eye daisies have finished, the knapweed is fluffing out and the yellow rattle pods are rattling in the breeze. Each fading flower head holds next year's meadow, and collecting some of it yourself is one of the cheapest, most satisfying ways to keep a wildlife-friendly garden or small meadow going. Seed taken from your own patch, or from a nearby meadow on similar soil, is already adapted to your conditions. It also keeps the local genetic character of an area intact, which matters more than most of us realise.

The trick is to collect at the right moment, on the right sort of day, and to store the seed properly. Do that and you'll have strong plants next season. Rush it and you'll end up with mouldy packets and a lot of wasted effort.

Knowing when seed is ripe

Every species gives its own signal, and learning to read them takes a season or two. The general rule is to collect just before the seed would fall naturally — not after. Once it has shed, the plant has already done your job for the birds and the ants.

• Ox-eye daisy: the central disc turns from yellow to brown and the whole head becomes dry and brittle; the small dark seeds are hard when you press them.
• Yellow rattle: the papery capsules go brown and rattle audibly when shaken. They open quickly, so check every couple of days.
• Common knapweed: the purple florets fade and the head becomes a fluffy brown tuft, with black seeds sitting at the base.
• Field scabious: heads dry to a pale grey-brown and the seed drops at the lightest touch, so hold a bag underneath.
• Meadow buttercup, ragged robin, betony, bird's-foot trefoil and selfheal: wait until the stems brown and the seed shakes loose into your palm.

If seed is green, soft or damp, leave it. Immature seed rarely ripens after picking and often rots in storage.

Collecting on a dry day

Choose a dry, breezy morning once the dew has lifted, or early afternoon. Damp seed is the enemy of a good packet. Take paper bags or envelopes, sharp snips, a basket and a permanent marker.

For species with loose seed, bend the stem over a bag and tap gently — most of it will fall in. For plants that hold their seed in pods or capsules, cut the whole stem and put it head-down in a paper bag, then leave it somewhere airy to finish opening. Keep one species per bag; mixing seed is the fastest route to a mystery meadow you didn't plan.

Never collect from land that isn't yours without asking. On a wild site, take no more than a tenth to a third of the seed from any one colony, leave plenty for wildlife, and never dig plants up.

Drying, cleaning and labelling

Spread your haul thinly on newspaper or in open paper bags in a dry, airy room away from direct sun. Plastic bags and tubs trap moisture and turn seed mouldy within days. Leave everything for a week or two, turning gently now and then.

Label as you go, not later. Memory is a poor record keeper, and a packet marked only "seed, August" is almost useless by March. Write on each packet:

• The species name, common and botanical if you know it
• The place it came from
• The date you collected it
• Anything else worth knowing — soil type, whether it was a wet or dry spot, how much you gathered

Once dry, rub the heads between your fingers to release the seed and sieve out the chaff. Small insects often hitch a lift, so leave packets open for a few days, or freeze the seed for a week to deal with any larvae.

Storing seed through the winter

Your labelled paper packets want a cool, dark, dry place — a lidded tin in a shed, a box in the garage, the salad drawer of the fridge. Add a small sachet of silica gel if the space is at all humid, and keep everything well away from mice, who find seed packets irresistible.

An airing cupboard is too warm and the kitchen is too damp. A steady temperature matters more than a cold one. Most meadow species stay viable for two to three years, but germination drops with every season, so sow what you collect rather than hoarding it.

Sowing, and leaving some behind

Yellow rattle is the exception to almost every rule: its seed loses viability quickly, so sow it fresh in autumn onto short, open turf where it can make contact with the soil. Most other meadow perennials are happy with an autumn sowing too, and many need a spell of cold to break dormancy. A light raking, a scattering and a gentle tread to firm the seed in is usually enough.

Finally, don't clear every seed head. Goldfinches, linnets and a host of beetles and bugs depend on standing seed through winter. Take what you need, leave the rest, and the meadow will look after itself — and you.