30-40 days to maturity
This herb can be easy to cultivate in United States Department of Agriculture Plant Hardiness Zones 4 to 9. In zone 4, it needs winter mulch and a well-drained sandy soil to survive. In zone 7, it can be harvested at least until the end of November. While it prefers full sun, moderately shade-tolerant, much more so than most herbs. In dry climates, it grows best in partial shade. It can also be easily grown as an indoor potted herb.
Lemon Balm requires light and at least 70 degrees Fahrenheit to germinate, so it is best to plant indoors or in Spring and not to cover the seeds. It requires consistently moist soil, do not let soil dry out in between watering. Lemon balm plants should be spaced between 12 and 15 inches (30 and 38 cm) apart.
Lemon Balm grows in clumps and spreads vegetatively as well as by seed. In mild temperate zones, the stems of the plant die off at the start of the winter, but shoot up again in spring. It can be easily grown from stem cuttings rooted in water, or from seeds. Under ideal conditions, it will seed itself prolifically and can become a nuisance in gardens.
It grows up to 2 feet tall in wild and usually 30-40 cm tall in container or pot. The leaves will reach 1-3 inches (2.5-7.5 cm) long and are broadly ovate with a lemon scent. At the end of the summer, little white flowers full of nectar appear, attracting bees.