Basil

This popular annual herb is easy to grow from seed sown indoors in spring, or even from young plants bought in supermarkets, and provides repeated harvests throughout the summer. When growing from seed, you can choose an array of flavours, leaf colours and textures, from sweet, aromatic Italian varieties to spicy Thai basils.

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Sow

Seeds are best started off indoors from late February to mid-summer. Fill a 7.5cm (3in) pot with seed compost, firm down and sow a few seeds over the top – most will germinate so only sow a few more seeds than you need. Cover with a thin layer of vermiculite, water gently and pop it into a propagator or cover the pot with a clear plastic bag, secured with an elastic band.

After germination, remove from the propagator or take off the bag, place in a warm, bright spot, such as a sunny windowsill, and water regularly to keep the compost moist. When the seedlings are large enough to handle and have their first true leaves, transplant into their own 7.5cm (3in) pot filled with multi-purpose compost.

Grow

If you don't have the time or space to grow basil from seed, you can simply buy a pot of basil from a supermarket. This will contain lots of plants, which can be separated and potted up individually. 

Keep basil plants indoors until all danger of frost has passed, then harden them off to gradually acclimatise them to outdoor conditions.

Choose a warm, sunny, sheltered planting site with well-drained soil, or a container filled with multi-purpose compost. You can keep a plant in a pot going all summer long by moving it into a slightly bigger container every time roots show through the drainage holes – plants could end up in a 20cm (8in) container. You can also plant basil in a greenhouse, where it makes a good companion to tomatoes.

Basil hates having wet roots overnight, so water in the morning if possible.

Keep plants bushy and productive by harvesting the shoot tips regularly, and remove any flowers that start to develop. Plants will die off at the end of summer, once temperatures start to fall.

Common problems

Aphids
Aphids

Look for colonies of greenfly on the soft shoot tips of plants or on leaves. They suck sap and excrete sticky honeydew, encouraging the growth of black sooty moulds.

Remedy

Use your finger and thumb to squash aphid colonies or use biological control in the greenhouse.

Slugs and snails
Slugs and snails

These feed on the young seedlings and you'll see the tell tale slime trail on the soil around your crop, as well as on the leaves.

Remedy

There are many ways to control slugs and snails, including beer traps, sawdust or eggshell barriers, copper tape and biocontrols.

Harvesting

Basil leaves can be harvested throughout the summer.

Remove leaves as required or harvest entire plants if lots of leaves are needed to make pesto or sauce.

If only a few leaves are required, remove the tops of plants to encourage bushy growth.

Recommended Varieties

Get involved

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