The common name for lemon balm – Melissa officinalis. An aromatic, sweet herb perennial related to the mint family and grown in herb gardens for seasoning purposes. The herb is also used in liqueurs and used historically as a medicine. Growing up to 2-feet tall with 2-lipped flowers during the late summer.
The leaves carry a lemon odor and flavor and considered a mosquito repellant plant. Lemon balm originated from the old-world but is widely naturalized in America. The preferred soils to plant the herb are fertile well drained clay or sandy loam.
Growing The Lemon Balm Plant
Lemon balm grows in clumps and spreads by seed as well as vegetatively. It can grow well in containers, outdoors and hydroponics. The herb should be planted 12-15 inches apart and will grow in a relatively wide pH range from 5.6 (acidic) and 9.0 (strongly alkaline) but the preferred range is 6.0 to 7.5.
While planting outdoors, plant in a full sun location. In a the dry climate, it grows best in partial shade. When growing it indoors, it grows satisfactorily under a high intensity fluorescent lamp. The plant will remain green during winter. The seeds germinate between 12 to 21 days.
When planting the herb indoors from seeds, plant the seeds for at least 8 weeks before the last date of spring frost. When planting the seeds outdoors, plant in late fall in full sun.
Lemon balm grows in zones 4 through 9. In US zone 7, lemon balm can be harvested until the end of November.
Its fragrant blossoms attract bees, butterflies and birds and being drought resistant makes it useful in xeriscaping.
Caring For Lemon Balm
Watering Melissa Officinalis
Water plants when the foliage begins to look wilted. When growing in high temperatures water at least once a week. When planted in cool and shady corners, they will require less water. When watering be sure to water deeply and saturate the roots.
Allow the top soil to dry before watering again as soggy soil may cause rotting of the plant. For container grown lemon balm may require daily watering.
Mulching The Herb
Adding 1-2 inches of mulch (compost or grass clipping) will benefit lemon balm and require less fertilizer. Mulch improves soil quality and helps moisture and cooler root temperatures during hot and dry weather.
Fertilizing Lemon Balm
Use an All Purpose Fertilizer during spring and after harvest if growth appears stunted. Follow the manufacturer’s directions when applying fertilizer. Do NOT over fertilize as excessive use can cause lush growth and reduces aroma and flavor.
Pruning And Trimming
Plants respond well to pruning. Remove spread blooms immediately to reduce the chances of the plant going to seed aggressively. Cut plants back to only a few inches tall several times during the growing season. This allows the herb to remain vibrant, and keep it from going to seed.
NOTE: As a rapid grower plants can easily overtake a whole herb garden, grow Lemon Balm in containers to prevent spreading.
Propagating From Cuttings
Lemon balm propagates easily via cuttings. Take cuttings during mid-summer and with 3 to 4 buds. Dip the cutting in a rooting someone and place the cuttings in a well draining soil out of direct sun. Give the plant some extra humidity by adding a “humidity dome” – easy to do with soda bottles.
Pests And Diseases
This sturdy, disease resistant plant does not like high humidity and soggy soils. Too much moisture leads to diseases such as powdery mildew and root rot. Water the plant early in the morning to allow time for the foliage to dry before evening. The best option is watering at the base or use drip irrigation to keep foliage.
Good spacing of 18-24 inches allows air circulation hence preventing diseases. Harvesting the plant leaves early also promotes air circulation. Spider mites, thrips and whitefly also enjoy dining on the plant.
Herbal Properties And Uses Of Lemon Balm
Used in treating a wide range of health disorders. Used to treat insect bites, stings and wounds when steeped with a little wine. Studies shows the herb as an effective aids for herpes. Further studies show when combined with chamomile, valerian and hops, as a remedy for insomnia and nervousness. The leaves are widely used for preparing teas while the essential oils find use in aromatherapy, steamy facials and skin cleansing.
Some people may experience contact dermatitis with the herb, test yourself first before using it in any way.
Some consider lemon balm a noxious weed and in other areas as an invasive plant. The herb self-sows freely, remove flowers if you do not need volunteer seedlings.