Lemon balm is a bushy perennial herb with oval, lemon-scented leaves with scalloped edges, and leafy spikes of creamy-white or pale purple flowers in summer. Fresh or dried leaves can be used to make herb teas, while leaves will give a lemony kick to salads, sauces, vinegars and fish dishes – they are best used fresh, rather than cooked. Dried leaves are added to potpourris and herb pillows.
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Named cultivars of this herb should be bought as ready-grown plants in spring, but ordinary lemon balm can be started from seed. Between March and May, sow a few seeds into pots of sowing compost and cover with a thin layer of perlite, vermiculite or finely sieved compost. Place pots in a heated propagator. After seeds have germinated, which can take up to three weeks, transplant seedlings to their own pots when they are large enough to handle.
Plants will thrive in any moist, well drained soil, in sun or partial shade or can be planted in pots filled with soil-based compost – a 20cm (8in) container would be ideal. Move outdoors when all danger of frost has passed.
Keep plants well watered, especially during dry spells in summer.
Growing to around 80cm (32in), traditional lemon balm makes a mass of green leaves, but there are several showier cultivars available and plants that have a more compact habit of growth.
In early summer, cut back variegated cultivars to encourage strongly coloured growth.
Cut back plants after flowering to encourage a fresh flush of leaves.
Rejuvenate congested clumps of lemon balm by lifting and dividing in the autumn.
Protect plants in pots from excessive winter wet by moving into a sheltered position and raising up onto pot feet to allow excess moisture to drain away.
Appears as a white powdery deposit over the leaf surface and leaves become stunted and shrivel.
Keep the soil moist and grow in cooler locations.
Pick fresh leaves as required throughout summer. Leaves for drying are best harvested before plants start to flower.
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