Bee balm or Monarda, a flowering genus from the Lamiaceae family, is indigenous to North America. There are more than 50 hybrid commercial varieties, although the hybrids are usually not as hardy as the wild varieties. These plants usually grow in meadows, forest clearings, and hillsides, up to altitudes of 5,000 feet.
The Monarda genus is named after Nicholas Monardes, a Spanish physician and botanist, who penned a three-part book in 1574 which described plants in the New World. He also was the first to publish books specifically about Native American flora in the late 1500s.
It got its common name from early settlers who were taught how to treat bee stings by smashing the leaves and rubbing them into affected areas by Native American people living around the eastern areas of the US. They also taught settlers how to make Oswego tea from the plants, which became a popular replacement for tea after the Boston Tea Party.
The species include perennial and annual herbaceous plants, growing to heights of 8–35 inches. The dark green serrated leaves are about 2-6 inches long and are hairless or somewhat hairy, growing on the square stems. The tubular flowers have narrow upper lips and wider lower lips. Wild varieties produce single flowers, while some hybrid varieties have double flowers. The flowers grow on stem-tops or between the axils on the stems. The colors vary, with wild varieties having pink, red, and light purple flowers. Hybrids occur naturally in the wild as well as being commonly cultivated. Seeds from hybrids do not germinate true to the parent.
The crushed leaves of these plants give out a spicy and fragrant essential oil. M. Didyma produced the highest output of essential oil among all the varieties examined in a study conducted by E.R. Spencer in 1974.
Growing these plants under full sunlight is best, although they also grow under partial shade in areas of intense summers. However, plants cultivated under partial shade might become leggy, stretched, and will not produce flowers as profusely.
These plants should be watered regularly every 7-10 days, particularly when they are first planted and during summer they won’t do well if over-or under-watered. Water them when the soil seems dry, always water the soil and avoid splashing water on the foliage to prevent problems such as powdery mildew.
They prefer low to moderate humidity as they are prone to powdery mildew infection in high humid conditions, particularly if grown in a place with poor air circulation.
These plants can tolerate cold and warm climates, with a low of -20°F, they prefer temperatures of 60-80°F during their growing season.
These plants like moist and fertile well-drained soil, particularly rich soil with organic compost with an alkaline pH of 6.5 to 8. They will not thrive in sodden or dry soils. If growing conditions are arid, adding mulch to the soil will help retain proper moisture. Poor drainage will result in root rot.
These plants generally do very well growing in containers, especially the dwarf varieties, but as they are fast growers they need repotting or division quite often, perhaps every year. When choosing a container ensure it has sufficient drainage capacity. Also, since they don’t have access to groundwater, potted plants will need frequent watering and monitoring. To repot, loosen the roots until the plant can easily slide out from the container and divide the plant if necessary. Prepare a larger container with rich soil and repot the plant, water it thoroughly.
These plants are propagated by seeds, division, and cuttings. Its prolific character divides the easier method of propagation. This also helps keep the plant full and healthy and must be done every couple of years.
Propagation by division:
Once the plant is 2-3 years old, it can be divided into several smaller sections to plant somewhere else in the garden or containers, dig up the root system, lift the plant and divide the roots with the stems into several sections. Prepare the soil in the garden or container with compost and plant the sections.
Propagation by cuttings:
Remove a cutting from new growth about 6 inches in length in spring, cutting it below a node. Remove all lower leaves, carefully plant them in a pot full of rich soil, and water them well. Regularly check the soil and keep it moist. When roots appear after 2-3 weeks, uncover the cutting and keep watering until the plant is big enough to transplant.
Propagating from Seed:
Propagating from seed needs some patience and time, but the rewards are worth it. The seeds must undergo cold stratification to germinate, either sow the seeds in your garden in the fall or store the seeds with damp soil inside a refrigerator for a month. In spring, select and prepare a spot in the garden with compost, remove the seeds and place them on the soil.
Rich, fertile soil is necessary for growing these plants. Add compost or humus every year in spring to provide the plant with the nutrients it requires or it can be fed with a balanced fertilizer.
Light pruning in spring by pinching off tips of new growth will make the plant bushy. Cutting down the plant a few inches in autumn will help promote new shoots in spring.
Sometimes the plant might produce very few flowers or none at all. This could be due to several factors, including high humidity, insufficient sunlight, and over-fertilization, or due to old age. High humidity can be corrected by providing it with good ventilation and monitoring your watering schedule. If the plant is growing in a shaded location, relocate it to a sunny spot. Cut back on feeding it until more flowers appear. If the plant is old, divide it to prolong its life and encourage new growth.
Powdery mildew disease commonly appears with high humidity and poor ventilation and causes wilted brown foliage covered with a gray powder. Prevent this from happening by increasing ventilation by pruning and dividing the plant. Avoid getting the leaves wet. Treat it with an appropriate fungicide, remove any plant debris and prune off infected stems and destroy them.
These plants are also susceptible to a few pests, including aphids, spider mites, whiteflies, and thrips. Apply insecticidal soap or neem oil to remove them. Stalk borers can also plague these plants, remove them by hand and sprinkle diatomaceous earth around the plants to deter them.