Sow in May

The last frost in most of the UK falls in early to mid-May, so everything tender can finally go outside. Sow direct: French beans, runner beans, courgettes, sweetcorn, squashes, pumpkins, salad leaves, beetroot, carrots, and most herbs. Plant out: tomatoes, cosmos, zinnias, and any half-hardy annuals you have raised under cover. Keep succession-sowing salads and quick crops.

Once nights are reliably above 8–10°C and the last frost has passed in your area. For most of the UK that's mid-May; in the South West and along the south coast you can sometimes plant out from late April; in Scotland and northern England, wait until late May or early June. Harden plants off gradually over a week before they go in.

Not at all — a May sowing of hardy annuals like cornflowers, calendula, and nigella will flower from late July through autumn, extending the season nicely. They won't be as tall or productive as autumn-sown plants, but they're still very worthwhile. Sow direct into well-prepared soil and water in gently.

May is an excellent month to sow plants for pollinators — borage, calendula, cosmos, phacelia, and verbena bonariensis all establish well now. They will be flowering by July or August, providing nectar through the critical late-summer gap when many garden flowers have gone over.