When can I sow basil seed in the UK?

Indoors from late April to mid-May; in a heated propagator from late March. Don't sow outdoors except on a sheltered south-coast bed in late May. Basil seedlings need 18°C minimum and hate cold wet soil — sowing too early gives leggy, stalled plants. Two or three pots indoors gives a household plenty.

Can I grow basil outdoors in the UK?

Only in pots, in a sunny sheltered south-facing position, from June to early September. The UK summer is borderline for basil — a cool wet July checks growth and a chilly August night below 10°C halts it. Greenhouse, polytunnel, or warm windowsill basil is more productive than outdoor in most of the UK.

Why is my basil bolting (flowering)?

Long days, heat stress, or the plant is mature. Bolting is normal — basil is an annual that's trying to set seed before frost. Pinch out the flower spikes as soon as they appear; this delays bolting by a few weeks. After several rounds of pinching, the plant will eventually flower regardless — that's the end of its useful life. Start a fresh sowing every 6 weeks if you want continuous supply.

What's the difference between sweet, Thai, and lemon basil?

Sweet (Genovese) is the standard pizza-and-pesto basil — broad leaves, classic basil flavour. Thai basil has smaller pointed leaves and a stronger aniseed note; the right basil for pho and Thai curries. Lemon basil has narrower leaves and a citrus-floral flavour; works in dressings and fish dishes. Sweet is the everyday; the others are worth a separate pot if you cook with them often.

How do I store fresh basil?

Treat cut stems like a small bouquet — stand in a glass of cold water on the kitchen counter, not in the fridge (cold blackens basil leaves). It keeps 4–5 days. For longer storage, blend whole leaves with olive oil and freeze in ice-cube trays. Drying ruins the flavour; freezing in oil preserves it.

Can I grow basil from supermarket pots?

Yes — the multi-stemmed pots at supermarkets are bunches of seedlings crammed together, struggling for root space. Tip the pot out, gently tease the seedlings apart, and pot them on individually (or in groups of 2–3) in fresh compost. Place on a sunny windowsill. Within two weeks they double in size and stop dying back.

Basilikum (süß)

Ocimum basilicum

Sow basil seed indoors from late April to mid-May; don't bother with outdoor sowings except on a sheltered south-coast windowsill. Basil is very frost-tender (RHS H1c) and hates cold wet soil — even a chilly summer night below 10°C checks growth. Grow in 1-litre pots on a sunny windowsill, in a greenhouse, or in a polytunnel; outdoor plants only thrive in pots in a sheltered south-facing position from June to early September. Pinch out flower spikes as they appear to keep the plant leafy. Pick young leaves regularly from the top; older leaves get bitter. Sweet (Genovese) basil is the kitchen standard; Thai basil for South-East Asian dishes; lemon basil for Mediterranean.

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