How to grow Lemon Balm in New Zealand
Lemon balm is a hardy, easy perennial herb in the mint family, with crinkled leaves that smell strongly of lemon when brushed. It makes a soothing tea, alone or with peppermint, and fresh leaves lift salads, desserts and fish. Its small white summer flowers are loved by bees. It self-seeds freely, so cut it back before it sets seed if you do not want it everywhere.
📖 Our full guide: How to Grow Lemon Balm in New Zealand
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| Northland | August to May | |
| Auckland | August to May | |
| Waikato & Bay of Plenty | August to May | |
| Central North Island | August to May | |
| Wellington & Lower North Island | August to May | |
| Nelson & Marlborough | August to May | |
| Canterbury | August to May | |
| Otago & Southland | September to April | Plant Sep to Apr so roots establish before the hard frosts. |
| Central Otago | September to March | Plant Sep to Mar so roots establish before the hard frosts. |
Where to plant
Lemon balm grows in full sun or part shade in most soils, as long as they hold some moisture and drain freely. In hot, dry spots the leaves can scorch, so afternoon shade or a place under a fruit tree suits it well. On clay, dig in gypsum and compost.
It forms dense clumps from shallow, creeping roots. It spreads less aggressively than mint, but it seeds itself around readily.
- Northland to Canterbury, including Wellington and Nelson and Marlborough: plant almost any time from spring to autumn, avoiding midwinter.
- Otago and Southland: plant from September to April so roots establish before the hard frosts.
- Central Otago: plant from September to March so roots establish before the hard frosts. Plants die back in the coldest winters and regrow in spring.
Choosing a variety
Common lemon balm (Melissa officinalis) is the usual form, sold as seed and plants. A golden-variegated form, Aurea, is grown as an ornamental and can be used in the same way.
How to plant
- Sow seed on the surface from September to March, pressing it in without covering, as it needs light to germinate. Keep it moist; germination takes 7 to 14 days at 18 to 25°C and can be patchy.
- Plant seedlings or bought plants about 20 to 30 cm apart.
- Water in and mulch with pea or lucerne straw to hold moisture.
Watering and feeding
Water regularly in dry weather, especially in pots, but do not keep the soil soggy.
Lemon balm needs little feeding. A liquid feed every few weeks in the growing season encourages fresh, leafy growth.
Pruning and care through the year
- Pick regularly, which keeps plants bushy.
- Cut the whole plant back by about half after flowering, or before seeds ripen, to stop it self-seeding and to bring on a flush of fresh leaves.
- Divide large clumps in spring or autumn.
Harvesting
Pick leaves or whole stems as needed from spring to autumn, from about two months after sowing. The flavour is best before the plant flowers. Use leaves fresh in tea, salads, desserts and with fish or chicken.
Leaves can be dried for tea, though they lose some scent. Fresh leaves keep a few days in the fridge in a damp cloth.
Growing in pots
Lemon balm grows well in pots at least 15 to 20 cm wide in quality potting mix, in sun or part shade. A pot also stops it seeding around the garden. Keep it watered but not waterlogged, and trim it often.
Companion planting
Lemon balm's flowers bring bees into the garden, which helps fruiting crops.
Good companions
- Tomato Its flowers bring in bees and other beneficial insects near summer crops.
- Brassicas A traditional companion that brings beneficial insects into the vegetable garden.
- Fruit trees It tolerates dappled shade under trees and its flowers attract pollinators.
Pests and diseases
Lemon balm has few pests. Powdery mildew in late summer is the most common problem.
Lemon Balm is rarely troubled by pests.
Diseases to watch for
- Powdery mildew White powdery coating on the leaves in late summer, especially in dry soil and still air. Cut plants back to bring on fresh growth.
Common questions
Does lemon balm spread like mint?
Less aggressively. It forms clumps from shallow creeping roots, but it self-seeds freely. Cut it back after flowering to stop it seeding, or grow it in a pot.
How do I make lemon balm tea?
Steep a handful of fresh leaves in just-boiled water for about five minutes. It is often combined with peppermint and sweetened with honey.
Why is my lemon balm seed not coming up?
Lemon balm seed needs light to germinate, so press it onto the surface rather than burying it, keep it moist and warm, and expect patchy germination.
Does lemon balm grow in shade?
Yes. It grows in sun or part shade, and in hot districts afternoon shade stops the leaves scorching.
Does lemon balm die in winter?
In cold winters it dies back to the ground and regrows from the roots in spring. In mild northern gardens it may keep some leaves all year.
Sources we checked: Kings Seeds NZ: Lemon Balm; Yates NZ: How to grow lemon balm; Herb Federation of New Zealand: Lemon balm.
