How to grow lemon balm
Melissa officinalis · Lamiaceae · Herb
When to plant lemon balm: the short answer
Start seeds indoors about 7 weeks before your last spring frost; plant out about 1 week before it; sow outdoors about 1 week before the last frost. Seeds germinate in soil from 60 to 80°F, fastest near 70°F.
Zone 5: plant out Apr 16 – May 3. Zone 7: plant out Mar 22 – Apr 8. Zone 9: plant out Feb 6 – Feb 23. See every zone.
Lemon Balm is a cool-season herb in the Lamiaceae family, grown either from a direct sowing or from transplants. It wants full sun, though it tolerates a little afternoon shade in hot regions and steady, even moisture. From sowing to first pick is about 70–90 days. It is one of the toughest crops here, standing through hard frost and often improving for it.
Grower’s note: A hardy mint-family perennial with a strong lemon scent, used fresh for tea. It self-seeds prolifically and creeps by root - deadhead it and grow it in a pot or a contained bed. Cut it back hard in midsummer for a flush of fresh leaves.
Sowing
Sow barely covered — the seed needs light to germinate, into soil between 60–80°F — germination is quickest near 70°F. It is slow and often erratic to germinate (7–21 days). For an early crop, start seed indoors about 7 weeks before your last spring frost and grow it under bright light.
Spacing & layout
Give each plant about 18″ along the row with roughly 24″ between rows. On a square-foot grid that is 1 per square foot. Allow at least 10″ of loose, workable soil for the roots. It grows well in containers at least 10″ deep.
Fitting it to your season
As a cool-season crop, lemon balm does its best growing in the mild weather of spring and fall and tends to bolt or turn bitter in summer heat.
Quick facts
Growth stages: how long lemon balm takes to grow
From sowing to first harvest takes roughly 70-90 days (10-13 weeks), with seedlings appearing after 7-21 days in soil around 70°F.
When to plant lemon balm
When to plant lemon balm by USDA zone
Dates worked out from each zone’s typical frost dates for 2026. Find your zone on the zone map, or pick your state below for dates from its own frost dates. Zones 11 and above are frost-free, so timing there depends on heat and rain instead.
| Zone | Last / first frost | Start indoors | Sow or plant out |
|---|---|---|---|
| Zone 3 | May 15 / Sep 15 | Mar 20 – Apr 3 | May 1 – May 18 |
| Zone 4 | May 10 / Sep 25 | Mar 15 – Mar 29 | Apr 26 – May 13 |
| Zone 5 | Apr 30 / Oct 5 | Mar 5 – Mar 19 | Apr 16 – May 3 |
| Zone 6 | Apr 15 / Oct 15 | Feb 18 – Mar 4 | Apr 1 – Apr 18 |
| Zone 7 | Apr 5 / Oct 25 | Feb 8 – Feb 22 | Mar 22 – Apr 8 |
| Zone 8 | Mar 20 / Nov 5 | Jan 23 – Feb 6 | Mar 6 – Mar 23 |
| Zone 9 | Feb 20 / Nov 30 | Dec 26 – Jan 9 | Feb 6 – Feb 23 |
| Zone 10 | Jan 30 / Dec 15 | Dec 5 – Dec 19 | Jan 16 – Feb 2 |
Compare with the other herbs: when to plant herbs, by zone.
Companions
Broccoli, Cauliflower
No strong antagonists recorded.
Common problems
Pests: aphids, spider mite, thrips.
Diseases & disorders: powdery mildew, septoria leaf spot, root rot.
Same family (Lamiaceae)
Rotate these so they don’t follow each other in the same bed year to year.
Questions gardeners ask
When should I plant lemon balm?
Start seeds indoors about 7 weeks before your last spring frost; plant out about 1 week before it; sow outdoors about 1 week before the last frost. Seeds germinate in soil from 60 to 80°F. The table on this page gives dates for each USDA zone, and the planting calendar gives dates for your own state or ZIP code.
How long does lemon balm take to grow?
About 70-90 days from sowing to the first harvest. Seeds germinate in 7-21 days, fastest in soil around 70°F.
How much sun does lemon balm need?
It needs six or more hours of sun for the best growth, though four to six hours in partial shade is enough.
What soil pH does lemon balm need?
A soil pH between 6.0 and 7.5. Test before adding lime or sulfur - see the soil pH and testing guide.
How far apart should I plant lemon balm?
Space plants about 18 inches apart in rows 24 inches apart, or 1 per square foot in a square-foot bed. Sow seeds about ⅛ inch deep.
Can I grow lemon balm in a container?
Yes. Use a container at least 10 inches deep with drainage holes and a good potting mix, and water more often than you would in the ground.
Figures are typical home-garden ranges from Cooperative Extension planting guides, cross-checked against multiple state sources. Your variety and conditions will vary.