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.

Jobs to do now
- Continue harvesting
- Remove flowers
Month by month
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.
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
'Genovese'
Ocimum basilicum 'Genovese'
The most popular Basil with large, bright green leaves on multi-branched stems. Height 45 cm. This Basil combines well with tomatoes and garlic, is ideal for pesto, and perfect in pasta sauces and salads. The basil for Salad Caprese with alternating layers of tomato, mozzarella and basil.
'Mrs Burns Lemon'
An improved form of lemon basil, more robust with larger leaves and a stronger lemon flavour. All culinary basil uses, but particularly good with fish or chicken. Excellent in South-East Asian dishes.
'Purple Ruffles'
Ocimum basilicum var. purpurascens 'Purple Ruffles'
One of the best performing purple Basils with ruffle-edged leaves and pink flowers. Flavour and form is similar to Genoese. Gives added colour to salads and in rice and pasta dishes.
'Siam Queen'
A slightly darker toned Basil giving the correct, more pungent flavour to Thai and South- East Asian Cooking. Siam Queen is a larger leaved variety, Thai Basils respond to warmth
Greek
Ocimum minimum
A small leaved, dense form, one of the ‘Bush Basil’ group. Height 30cm. It has an intense Basil flavour with reduced anise overtones, easy to grow and ideal for containers.
Common problems
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
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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.
Get involved
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