Herb
Lemon Balm
Melissa officinalis · Lamiaceae
Also called: Balm, Sweet balm, Bee balm (regional, not to be confused with Monarda)
Lemon Balm (Melissa officinalis) is a moderate-water herb well suited to Tucson and the low desert. It's a fast-growing herb. Expect white to pale yellow blooms late spring to summer.
Lemon Balm at a glance
- Water use
- Moderate (established)
- Sun
- Partial shade is best in Tucson; full morning sun with afternoon shade prevents leaf scorch. Tolerates more sun in cool months but needs protection from intense summer sun.
- Mature size
- 1.5-2 ft tall, 1.5-2 ft wide (bushy clumping perennial; can spread).
- Growth rate
- Fast
- Bloom
- White to pale yellow, Late spring to summer (small white-to-pale-yellow flowers).
- Cold hardiness
- Cold-hardy perennial that survives Tucson winters and frost (may die back and re-sprout); the challenge is intense summer sun and heat, which scorch foliage without shade and adequate water.
- Soil
- Moist, well-drained soil amended with compost/organic matter; tolerates alkaline desert soil. Containers help control its spreading habit.
- Native range
- South-central Europe, the Mediterranean, and Western Asia; not native to the Sonoran Desert
- Best used as
- Culinary/tea herb (lemon-scented leaves for teas, salads, desserts), Medicinal/calming herbal tea, Pollinator plant, Container herb (recommended to contain spread)
- Wildlife
- Flowers attract bees and pollinators (Melissa means honeybee); lemon scent tends to deter some pests and mosquitoes.
- Toxicity
- Edible and non-toxic to humans; generally regarded as safe and non-toxic for dogs and cats.
How to grow Lemon Balm in Tucson & the low desert
Watering
Likes consistently moist soil; water regularly, roughly 2-3x/week in mild weather and more in summer heat or containers. Mulch to retain moisture and cool the roots; do not let it dry out fully.
Fertilizer & nutrients
Light feeder; incorporate compost at planting and side-dress with a balanced or nitrogen-leaning fertilizer (e.g., fish emulsion) every 4-6 weeks during active growth for lush, flavorful leaves.
Pruning & care
Harvest and shear regularly to promote fresh tender growth and prevent legginess; cut back hard after flowering to refresh. Remove flowers to keep leaves flavorful and limit self-seeding.
Notes
In Tucson, grow as a partly shaded perennial: plant transplants in fall or spring and site it where it gets morning sun and afternoon shade with regular water. It can spread by seed and roots, so growing in a container or contained bed is wise. Shear frequently for the best leaves; it may look ragged in peak summer but rebounds in cooler weather.
Sources: University of Arizona Cooperative Extension; Pima County Master Gardeners