Why pots are the sensible place to start

Native wildflower seed is cheap, plentiful and often maddeningly slow to reveal itself. Sow it straight into a meadow and you will spend the following spring squinting at a patch of soil, unable to tell a corncockle seedling from chickweed. Pots give you control. You can label precisely, water carefully, protect the seed from mice and slugs, and give the plants the cold spell many of them need without losing them in the mud.

Three species make an excellent starting set: corncockle, oxeye daisy and yellow rattle. Between them they cover the straightforward annual, the dependable perennial and the awkward, fascinating one that opens up the world of meadow-making.

Meet your three starters

• Corncockle (Agrostemma githago) is a tall, loose-limbed annual with magenta flowers from June to August. Its seed is large and easy to handle, it germinates in a fortnight, and it will often self-sow once established. Do handle the seed with some care and wash your hands afterwards, as all parts of the plant are poisonous.
• Oxeye daisy (Leucanthemum vulgare) is a tough, long-lived perennial for rough grass and sunny borders. The seed is dust-fine, needs light to germinate and can take three or four weeks to appear. Sown in autumn, it will flower in its second summer.
• Yellow rattle (Rhinanthus minor) is the meadow maker. It is an annual that parasitises the roots of grasses, weakening them enough to let wildflowers through. The seed must be fresh — buy it dated from the most recent harvest — and it needs a long cold spell and a host grass to germinate well. Once you have rattle, you have a meadow.

Sowing: lean compost, thin sowing and the right depth

Use a lean, free-draining mix: peat-free multipurpose compost blended with about a third horticultural grit or sharp sand. Do not feed it. Wildflowers come from poor ground, and rich compost produces soft, floppy growth that will not stand up to a British summer.

Fill 9cm pots or a seed tray, firm gently and water well, then let them drain. Sow thinly — thicker sowings damp off. Then treat each species slightly differently:

• Corncockle: press seed into the surface and cover with about 2cm of compost. Sow from late March to April, or in September. Keep at around 15–20°C. Germination in 10–14 days.
• Oxeye daisy: surface sow and press gently into the compost without covering. It needs light. Keep cool and moist; germination in two to four weeks.
• Yellow rattle: surface sow, press in and scatter a thin layer of grit over the top. Sow in September or October. Germination is often erratic and may not happen until February or April.

Label every pot with the species and the date. Fine seed dries out in minutes, so water from below with the pot standing in a tray, or use a very fine rose from above.

Stratification and the cold spell

Many native species need a period of cold, damp conditions to break dormancy. This is called stratification, and there are two easy ways to provide it.

• The fridge method: mix seed with a little damp sand or vermiculite, seal in a labelled bag and keep at 1–5°C for four to six weeks, then sow as normal. Check it regularly for early germination.
• The outdoor method: sow into pots in autumn, water, cover with fine mesh and leave them outside against a wall. Rain and frost do the work for you. The mesh matters, as mice are very fond of corncockle seed.

Yellow rattle benefits from at least six to eight weeks below 5°C. Keep the pots moist but never waterlogged through winter, and check them in mild spells.

Pricking out and caring for young plants

Move seedlings on once they have their first set of true leaves, which look quite different from the seed leaves. Hold them by a leaf, never the stem, and ease them out with a pencil or a small dibber into 9cm pots of the same lean mix. Water from below and keep them cool, bright and frost-free — a cold frame or unheated greenhouse is ideal.

Feed sparingly, if at all. A single weak seaweed feed is plenty if leaves look pale. Watch for slugs, mice and damping off; the latter is prevented by good airflow and not overwatering.

Yellow rattle is the exception to normal pricking out. Do not move it into plain compost. Sow or pot it alongside a pinch of fine grass seed, such as bent or fescue, so its roots can find a host to attach to. Without grass, the plant will sulk and fade.

Hardening off and planting out

Harden young plants off for ten to fourteen days before planting out, putting them outside by day and bringing them in at night, or using a cold frame with the lid propped open. Autumn is the best time to plant perennials and rattle; corncockle can go out in spring after the last frost.

Choose sunny, free-draining spots. Oxeye daisy settles happily into short grass or a border edge — mow around it in its first year. Plant yellow rattle into an established grass sward that has been kept short, water it in and hold off the mower until it has knitted in, then let the grass grow and watch the flowers arrive. Keep the pots going as a nursery, too, and you will have seed to sow again next autumn.