Growing Basil in Ireland

Basil is easy to buy from the shops, but you can grow a wider range of types yourself at a lower cost to you and the environment.  The type sold in non-returnable pots is usually sweet basil suitable for salads and pesto, but there are also cinnamon and lemon basil, varieties with purple leaves that look great in green salads and spicy or liquorice-flavoured Thai varieties that combine well with Asian food.

Basil is a fast-growing, tender annual that needs lots of light, heat, and water.  Being very sensitive to cold, it is an ideal candidate for tunnels and glasshouses, especially in our unpredictable summers.  It improves the flavour of tomatoes when served with them, and some say that it also does so when grown with them.  It grows best in well-drained acid or neutral soil.  Sow a succession of crops, but just a couple of plants each time is enough for regular use unless you want extra for pesto.  Either sow them in cell-trays or in situ in the greenhouse soil, thinning them to single plants as soon as they are big enough to see.  Use scissors to avoid root disturbance.  Thin or place the plants to about 30 centimeters apart.  Harvest leaves as soon as the plants are about 20 cm tall, by cutting off shoot tips.  Leave on the lower leaves until you discard the plant; they will produce the food to grow new shoots from the lower side-buds.  Even if you need no basil, cut off the tips to prevent flowering (which makes the leaves bitter) and encourage fresh sprouts to grow.  Surplus leaves can be either frozen for later use or composted, and the flower-buds are edible too.

Mizuna (horticulturalist Peter Whyte gives some tips for Greenhouse users)

Mizuna is one of the oriental greens that Europeans should grow and eat more. It’s best grown rather than bought because it needs to be eaten right after harvesting for maximum flavour and nutrient value, though it will keep for a couple of days in the fridge. Like lettuce, you can sow seed little and often all year round in a glasshouse or polytunnel. September sowings will produce deeply cut leaves up to April or May: single leaves can be cut off after about three weeks and whole heads after six to eight weeks.
Mizuna likes moist rich soil, so dig in plenty of compost or other organic matter before sowing. Sow the seed about a centimetre (half an inch) deep in drills about 30cm (12 inches) apart. Protect the seedlings from slugs. Keep it well watered and ventilate on sunny days – it is prone to bolting in hot dry conditions. If it does bolt remove the flowering stems right away to keep it leafy and sow another batch to replace it. Don’t worry if it wilts after a frosty night: it is hardy and usually recovers. It is a member of the cabbage / brassica / crucifer family so don’t sow it in the same ground as any of its relatives for at least three years to prevent disease build-up
Mizuna has a milder flavour than either mibuna or rocket, and is good in mixed salads. Like spinach it can be steamed, boiled or stir-fried but it shrinks a lot, so harvest plenty. ‘Kyoto’
is a good variety to try.