Lemon balm
Lemon balm is a bushy perennial herb with deliciously lemon-scented leaves and creamy-white or pale purple flowers in summer. It is vigorous and easy to grow in sun or light shade. The leaves give a lemony kick to salads, sauces and fish dishes, and make a refreshing herb tea.
Jobs to do now
- Harvest leaves
- Water in dry spells
Month by month
Sow
Lemon balm (Melissa officinalis) is easy to grow from seed in spring, but named varieties are only available as ready-grown plants.
Sow seeds indoors from March to May, scattering a few seeds into a small pot or tray of seed compost. Cover with a thin layer of perlite, vermiculite or finely sieved compost, then water gently. Place the pot in a heated propagator or cover with a clear plastic bag and place in a warm spot.
As soon as seedlings appear, which can take up to three weeks, take the pot out of the propagator or remove the cover. Prick out the seedlings into individual pots when they are large enough to handle.
Transplant the young plants outdoors once all danger of frost has passed.
Grow
Traditional lemon balm is a vigorous plant that eventually makes a large leafy clump, and sends up flower stems that can reach 80cm (32in) tall. There are several cultivars too, with variegated leaves or a more compact form. The flowers are a magnet for bees.
Keep plants well watered during dry spells in summer, and cut back after flowering to encourage a fresh flush of leaves.
Lemon balm will self-seed readily, so if you don’t want more plants, remember to remove the faded flowers before they set seed.
With variegated cultivars, cut back in early summer to encourage fresh, strongly coloured shoots.
Lemon balm is a long-lived plant than can form a congested clump – so lift and divide every few years in autumn to rejuvenate plants.
Protect plants in pots from excessive winter wet by moving them into a sheltered position and raising up on pot feet to allow excess rainfall to drain away easily.
Plant
Water the plants well, both before and after planting.
Choose a planting site in sun or light shade, with soil that is moist but drains freely. Lemon balm can also be planted into large pots filled with soil-based compost – a 20cm (8in) container would be ideal.
Harvesting
Pick fresh leaves as required throughout summer. Leaves for drying are best harvested before plants start to flower.
Recommended Varieties
All Gold
Melissa officinalis 'All Gold'
All the leaves of this variety are yellow-gold which makes this a nice foil plant for other green or purple herbs. All the fresh culinary uses of the Balm family apply. Grow in semi-shade to prevent scorching. ‘All Gold’ is less prone to self-seeding.
Aurea
Melissa officinalis 'Aurea'
The variegated form of Lemon Balm with irregularly yellow splashed leaves often on the serrated leaf edges. ‘Aurea’ is as lemony as other lemon Balms so is interchangeable in the kitchen.
Common
Melissa officinalis
This is the all-green generic form and a common hardy mainstay in the herb garden for fresh use in teas, summer drinks, salads, salsas, fruit cups and other deserts, cooked it’s flavour vanishes.
Dwarf
Melissa officinalis 'Compacta'
This is a dwarf form of green Lemon Balm and only grows to about 30cm. It’s a sterile form so no self-seeding and propagation is by stem cuttings. All Balm culinary uses. Ideal for small pots.
Common problems
Powdery Mildew
Appears as a white powdery deposit over the leaf surface and leaves become stunted and shrivel.
Remedy
Keep the soil moist and grow in cooler locations.
Get involved
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