Perennial Herb · zones 3–9 · 5 varieties

Lemon Balm

Melissa officinalis

Lamiaceae — the same plant family as english lavender, basil, bee balm, mint and 11 more here. Relatives share pests and diseases, which is why rotation plans group by family.

Lemon Balm (Melissa officinalis) is a perennial herb for USDA zones 3–9. It wants full sun and pH 6–8 soil, with about 1 in of water weekly. It matures in about 90–120 days from sowing, or 60–80 days from setting out a transplant. Watch for aphids and powdery mildew. Below: its full sourced profile from 5 extension sources, plus a planting calendar timed to your frost dates.

Zones 3–9 — USDA USDA
Sun Full sun
Water Moderate
Matures 60–80 days — from transplantest from transplant
Mature size 2–3 ft
Spacing 16–24 in
Soil pH 6–8
Frost Very hardy
When to plant lemon balmtypical · zone 6b
Your zone
…or your ZIP, for your real frost dates

Growing
Establishing
Harvest
Flowering
Dormant

Typical dates for zone 6b — set your zone or ZIP for yours. This calendar assumes the crop is started indoors. Timing is a guide from the crop's sourced growth stages; confirm with your local frost dates and extension before you sow.

Growing lemon balmevery fact says where it came from

What we will not put a number on

We do not give a feeding rate for this crop, and that is deliberate rather than a gap. The figures published by extension services are pounds of nitrogen per acre for a production field — they do not convert safely to a raised bed or a pot without knowing your soil test and your fertilizer's analysis, and guessing errs toward burning roots. It is also why every chart you find online disagrees with the next one.

We give watering as a depth per week rather than gallons per plant, because that is how it is actually measured and how the published figures are written. A gallons-per-plant number depends on your spacing, your soil and whether the plant is in a pot — so it would look more precise than it is.

Site & soil

Hardiness zones
3–9
Sun
Full sun
Soil pH
6–8
Soil texture
Loam, Sandy, Clay, Well drained
Frost tolerance
Very hardy

No published figure for the temperature frost starts to hurt it and the temperature that would kill it. We looked — where a number is missing here it is missing from the research, not skipped. The crop’s frost and heat tolerance above still applies.

The plant

Mature height
2–3 ft
Mature spread
1.5–3 ft
Growth rate
Fastest
Spacing in row
16–24 in
Between rows
24–36 inest
Planting depth
0.125–0.25 in
Container size
2–5 gal — low end is the minimum, high end is betterest
Support
Self-supportingest
Grown from
Seed, Division, Cutting, Root cutting, Layering

Water & feeding

Water needs
Moderate
Water per week
1 in/wkest
Critical water
Establishmentest
Feeding
Low

Timing & fruiting

Days to maturity
90–120 days from seed · 60–80 days from transplantest
Harvest cues
Rapid leaf growth

Planted again for autumn

Set plants out by
late Aug typical · zone 6b

60 days to maturity from setting a plant out — that is what our sources measure for this crop, so this is a date for planting out and not a sowing date, counted back from the first frost above. Not published for anywhere in particular: it is your own frost date and this crop's own figure, which is why it works wherever you are. A days-to-maturity figure is a catalog number for a good season rather than a promise, and a cold month moves it.

Edible parts per source: leaf, flower.

What tends to go wrongmost-cited first
PestsAphidsSpider mites
DiseasesPowdery mildewRoot rot

Compiled from the extensions cited below. Which ones actually show up depends on your region — your extension's local list is the last word.

⚠ Reported toxicityverbatim from cited sources

Different parts differ — the edible part is the leaf and flower; the notes below flag other parts or preparations.

PetsNon toxic to dogs, Non toxic to cats, Non toxic to horses

Recorded exactly as the source states it — not medical or veterinary advice. If a person or animal may have eaten a toxic part, call Poison Control (1-800-222-1222) or your vet / the ASPCA line (888-426-4435).

All 5 varietiesthe ones with their own page are linked
Variety TypeHabit DaysColorWhat it is known for
All Gold Golden Bush 60–80 Yellow Hayefield describes this asgrown to look at
Common Green Bush 70–90 Green Companion Plants describes this asdrops seed and comes back on its own · draws bees and butterflies · grown for cooking
Compacta Compact Dwarf 60–80 Green
Lime Balm Green Spreading 60–80 Green Farmacie Isolde describes this asgrown for cooking
Variegated Variegated Bush 60–80 Bicolor NC State Extension records this asgrown to look at
Sources5 cited · 5 organizations
  • NC State Extension
  • University of Illinois Extension
  • University of Minnesota Extension
  • University of Wisconsin-Madison Division of Extension
  • Utah State University Extension

We compile bare facts from these university-extension and horticultural sources, never copied prose. 13 of the 20 values on this page carry a citation. The rest are marked est; hover one and it says why — either nobody publishes a figure we could point at, or a person set it and attached no source. Figures vary with climate and seed source; confirm with your local extension before you buy.

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