Lemon verbena

Quick facts

Category

herbs woody

Difficulty

intermediate

Days to harvest

120 to 180 days

Harvest type

continuous production over weeks or months

Spacing

80 cm between plants

Environment

Temperature

10–30°C

pH

6 to 7.5

EC (hydroponic)

1 to 1.6 mS/cm

Daily light

18 to 28 mol/m²/day

Climate and zones

USDA zones

8 to 11 (winter low around -12°C or warmer)

Frost tolerance

frost sensitive (dies at first frost)

Season

warm (summer crops, frost-sensitive)

Viable growing environments:

• outdoor in growing season (annual)
• unheated greenhouse / hoop house
• heated greenhouse
• indoor (heated home)

USDA zone bounds reflect outdoor year-round survival. Anywhere outside the bounded zone range, this crop still grows as an annual in the warm months (outdoor_seasonal), under cover (greenhouse), or indoors under lights.

Growing systems

Lemon verbena works in:

• media bed (ebb and flow)
• soil bed
• drip / Dutch buckets

Growing media

The substrate the roots sit in. Choice depends on the system (clay pebbles don't fit NFT channels; rockwool isn't used in media beds) and the crop (lemon verbena works in the media listed below).

Bacterial surface area matters for aquaponics: clay pebbles, lava rock, and pumice double as biofilter substrate. Low-surface media (rockwool, perlite, pea gravel) work in hydroponics but need a separate biofilter in aquaponics.

Nutrient demand by stage

NPK ratios are relative weights at each growth stage; the nutrient mix calculator scales them to absolute grams or ml. EC targets shift through the plant's life: seedlings need a much lighter solution than fruiting adults.

Aquaponics suitability

Compatible with typical aquaponics nutrient profiles. Fish waste provides enough nitrogen for healthy growth; supplemental potassium, calcium, and iron may still be needed depending on fish stocking density.

Care notes

A rewarding container herb for greenhouse or indoor growing. Large container (15 L) because the plant becomes a woody shrub. Well-drained media (perlite, expanded clay). EC 1.0-2.0 mS/cm. pH 6.0-7.0. Temperature: 15–30°C (frost-sensitive; leaves drop below 5°C, but the woody stems survive brief frost to about -5°C and releaf in spring). Full sun (DLI 16-25 mol/m2/day). In cold climates, bring the container indoors for winter; the plant goes dormant, drops its leaves, and looks dead, but resprouts from the woody stems in spring if kept frost-free. Harvest leaves throughout the growing season by pinching stem tips or stripping individual leaves. For tea: steep 5-8 fresh leaves in hot water, or dry the leaves at 35–40°C for storage. The dried leaves retain the lemon scent for 6-12 months in sealed jars. Propagation by semi-hardwood stem cuttings (taken in late summer). A single well-maintained plant provides enough leaves for a household's tea consumption year-round.

Further reading

• Best crops for hydroponic beginners
• The Kratky method: grow lettuce with zero electricity