When to plant Basil in the UK

Sow basil seeds thinly on the surface of moist seed compost in trays or pots. Cover lightly with vermiculite or a fine layer of compost, as they need some light to germinate. Keep at 18–24 °C in a bright spot. Germination takes 7-14 days. Do this late March to early April.

Once seedlings have their first true leaves, prick them out into individual 7–9 cm pots filled with multi-purpose compost. Handle gently by the leaves to avoid stem damage. Keep in a warm, bright location. This step occurs around mid-April to early May.

When roots fill the small pots, pot on into larger containers (e.g., 12–15 cm pots) to encourage strong growth before transplanting outdoors. Use a well-draining compost mix. This is done late April to mid-May.

Gradually acclimatise plants to outdoor conditions over 7–10 days before transplanting. Start with a few hours in a sheltered spot, then increase the time outside each day. Protect from strong winds and cold nights. Harden off around mid-April to early May.

Plant basil outdoors in a sunny, sheltered spot with well-drained soil after all risk of frost has passed. Space plants 25 cm apart. Water in well and consider using cloches or fleece if nights are cool. Transplant mid-May to late May.

Water basil regularly to keep the soil consistently moist but not waterlogged. Feed every 2-3 weeks with a balanced liquid fertiliser to support leafy growth. Start feeding from late May and continue until late October.

Regularly pinch out the growing tips and any flower buds to encourage bushy growth and prevent bolting. Harvest leaves from the top down, taking no more than one-third of the plant at a time. Do this from early June onwards.

Harvest basil leaves regularly once plants are well-established. Pick in the morning for the best flavour, using scissors or pinching off stems above a leaf pair. Harvest from early July until late September for continuous supply.