Lemon balm is a hardy, fast-growing member of the mint family with soft, crinkled leaves and a bright lemon scent. It makes a fragrant tea, flavors desserts and drinks, and draws bees when it flowers. Like mint, it spreads readily and can self-seed everywhere if left alone, so it is best kept in check. This page covers when to plant, spacing, care, common problems and how to harvest lemon balm.
Lemon Balm at a glance
| Type | Herb |
|---|---|
| Season | Perennial |
| Sun | Full sun to part shade |
| Plant spacing | 18 in |
| Row spacing | 18 in |
| Per square foot | 1 |
| Seed depth | 0.05 in |
| Days to maturity | 70–90 from seed |
| How to start | Plant lemon balm in spring after your last frost, or in early fall. |
| Water | 1 in per week |
These are the same numbers our plant spacing, square foot and harvest date calculators use. See every crop in the plant database.
When to plant lemon balm
Plant lemon balm in spring after your last frost, or in early fall. Start seed indoors 6 to 8 weeks before the last frost; the seeds are tiny and need light to sprout, which takes 1 to 3 weeks. Most gardeners start with a nursery plant or a division from a friend. Lemon balm is a perennial in roughly zones 4 to 9 and dies back to the ground in winter before regrowing in spring.
Find your last frost with the frost dates by ZIP code tool and check your zone with the growing zone finder.
How to plant lemon balm
- Choose sun or part shade. Lemon balm grows in full sun but appreciates afternoon shade in hot climates, where leaves can scorch.
- Use average soil. It tolerates most soils but grows best in moist, well-drained ground with some compost.
- Sow on the surface. If starting from seed, press it onto moist mix without covering it, since it needs light to germinate.
- Contain it. Grow lemon balm in a pot or sunk bottomless container, and cut off flowers before they set seed, or it will pop up all over the garden.
Caring for lemon balm
Water about an inch a week and more for plants in pots in hot weather. Lemon balm tolerates short dry spells but the leaves are best when the soil stays evenly moist. The garden watering calculator turns this into gallons.
It needs little feeding; a layer of compost each spring is plenty. Cut plants back by about half in midsummer, before or just after flowering, to refresh the foliage and prevent seeding. Divide clumps every 3 to 4 years in spring to keep them vigorous.
Companion plants
| Grow nearby | Cabbage-family crops, tomatoes, squash, fruit trees, other herbs |
|---|---|
| Keep apart | Nothing serious, but keep it away from small, delicate plants it can crowd out |
Lemon balm flowers attract bees and other pollinators, which helps nearby fruiting crops. Its scent is said to help deter some pests, but it is best grown in its own pot or corner so it cannot take over. Check other pairings with the companion plant finder.
Common problems
| Problem | What you see | What to do |
|---|---|---|
| Spreading and self-seeding | Seedlings appear all over the bed | Cut off flowers before seeds form and grow in a container or sunk pot. |
| Powdery mildew | White powdery coating on leaves, common in humid weather | Improve airflow, cut back crowded stems and avoid wetting leaves. |
| Leaf scorch | Brown, crispy leaf edges in hot sun | Give afternoon shade and keep the soil evenly moist. |
| Leggy, flowering plants | Tall stems with small leaves after flowering | Cut back by half in midsummer for a flush of fresh leaves. |
| Aphids and spider mites | Clusters of insects or speckled leaves | Rinse plants with water. See the pest identifier. |
Not sure what you are looking at? The plant problem identifier ranks likely causes from the symptoms you see.
When and how to harvest
Start picking once plants are 6 to 8 inches tall. Snip stems just above a pair of leaves, which makes the plant branch. Leaves have the best flavor and scent before the plant flowers, so harvest regularly in spring and early summer. You can take up to two-thirds of the plant at once and it will regrow.
Use fresh leaves for tea, drinks and desserts. The scent fades quickly when dried, so dry leaves fast in a warm, airy place out of sun, or freeze whole leaves or chopped leaves in ice cubes. Fresh stems keep for several days in a glass of water.
Plan your lemon balm
- Plant spacing calculator: how many plants fit your bed
- Planting calendar: sowing and transplant dates for your frost dates
- Frost dates by ZIP code: your last spring and first fall frost
- Harvest date calculator: when your crop will be ready
Frequently asked questions
How far apart should I plant lemon balm plants?
Space lemon balm plants 18 inches apart in rows 18 inches apart. In a square foot garden, plant 1 per square foot.
How deep do I plant lemon balm seeds?
Lemon balm seed needs light to germinate, so press it onto the surface and barely cover it. Plants are set at the same depth as in the pot.
How long do lemon balm plants take to grow?
Lemon balm grown from a nursery plant can be harvested within a few weeks of planting. Seed-grown plants are ready in about 70 to 90 days.
How much water do lemon balm plants need?
About 1 inch of water a week, from rain and watering combined. Keep the soil evenly moist for the best leaves; it tolerates short dry spells.
Does lemon balm come back every year?
Yes. Lemon balm is a hardy perennial in about zones 4 to 9. It dies back in winter and regrows in spring.
How do I stop lemon balm from taking over?
Grow it in a pot or a sunk bottomless container, cut off flowers before seeds form, and pull any seedlings that appear.