Native to southern Europe, lemon balm has become a garden staple in much of the United States. Long used to calm and lift spirits, the oils of lemon balm are used for aromatherapy and the leaves are added to soups, salads, sauces, or vegetables. Dried leaves are mixed into potpourri.

This fast-growing perennial herb also makes a great addition to most gardens because it attracts pollinators. In summer, small white blossoms appear in clusters at the stem tips. While not showy, these flowers attract bees, butterflies, and hummingbirds.

Where to Plant

Select a location in full sun and well-draining soil with average moisture and a soil pH ranging from slightly acidic to slightly alkaline.

The herb garden is not the only place for lemon balm. Consider planting it near walkways to brush against its quilted green leaves and enjoy their pleasing scent.

As a member of the mint family, lemon balm is an aggressive grower. Unlike mint, however, spreading mostly occurs via seed dispersion and only partly via rhizomes. The self-seeding is easily controlled by deadheading the plant promptly after the bloom.

How and When to Plant Lemon Balm

To start lemon balm from seed, direct sow seeds after the last frost or start them indoors in small pots 5 to 6 weeks before your last average frost date. Sow the seeds ¼ inch deep and keep them evenly moist. Germination takes 5 to 10 days.

If starting the seeds indoors, give the seedlings plenty of light in a south- or west-facing window or under grow lights, otherwise they will become spindly. Harden them off before transplanting them in the garden after the last spring frost.

Space plants 8 inches apart.

Lemon Balm Care Tips

If you plant lemon balm in suitable conditions, it will take off without much effort on your part.

Light

For the most prolific blooms and highest oil content, plant lemon balm in full sun. In southern climates with hot summers, the plant fares better in part shade. However, too much shade causes the plant to become leggy.

Soil and Water

This herb tolerates poor soil conditions but grows best in well-drained soils with average moisture and a pH between 4.5 and 7.6.

Once established, the plants are drought-tolerant but appreciate supplemental watering during the summer heat. Soggy soil, on the other hand, encourages root rot.

Temperature and Humidity

The plant is very winter-hardy and survives winters as low as in Zone 3. In exposed locations in colder climates, it benefits from a layer of mulch during the winter.

High humidity does not impact the plant.

Fertilizer

Lemon balm grows even in soils with low fertility but if you harvest the leaves regularly, it is recommended that you use an all-purpose garden fertilizer every couple of months.

Pruning

Lemon balm tends to spread somewhat aggressively and often self-seeds. To prevent this, deadhead after flowering. Cutting the stems back hard after flowering will produce a fresh flush of leaves so you can start harvesting fresh young leaves again.

Potting and Repotting Lemon Balm

Lemon balm is a prime candidate for container growing because it limits its spread. Use a pot with large drainage holes and fill it with well-draining potting mix. Remember that potted plants need more frequent watering than plants in garden soil.

Although lemon balm is winter-hardy, at the lower end of its zone range, potted plants should be winterized to protect the roots. Bury the pot in the ground or place it in a larger pot to create an insulation silo.

Every year or two when the roots have filled the container, repot the plant to a larger container (one size up) with fresh potting soil. Instead of replanting it to a larger pot, you can also divide the plant.

Pests and Problems 

Lemon balm is rarely bothered by serious pest or disease issues. You might find aphids and spider mites on the plant. Wash them off with a strong spray from the hose before they become an infestation.

The plant is deer-resistant.

How to Propagate Lemon Balm

Because lemon balm is such a prolific self-seeder, it is rare for gardeners to have the desire to propagate the plant; instead, you are likely to find yourself pulling unwanted seedlings (which can be repotted or replanted in a new location).

Alternatively, divide a mature plant in the spring as the new growth starts. Dig up the entire clump and divide it into smaller sections with a spade. Every section should have a good amount of roots and new sprouts on it. Replant the sections in new locations at the same depth as the original plant. Water them immediately and keep them well-watered until they are established.

Harvesting Lemon Balm

Lemon balm is ready about 70 days after starting it from seed. Harvest the leaves when they are young and tender. Once the tiny white flowers appear, stop harvesting, as the leaves will become unpleasantly bitter. Cut the stems with the leaves early in the morning after the dew has dried.

To preserve large amounts of lemon balm, hang the stems upside down to dry in a cool, dark place. Once the leaves are crisp, separate them from the stems. Store the leaves in an airtight container.

Freeze lemon balm leaves in ice cubes to make colorful garnishes for lemonade.

Types of Lemon Balm

'Variegata'

Melissa officinalis 'Variegata' ('Aurea') has variegated green leaves splashed with golden yellow.

'All Gold'

Also known as ‘Gold Leaf’, this cultivar has striking golden foliage. The leaves are especially vibrant in spring and early summer and hold their color through the growing season.

'Lime'

Also referred to as lime balm, this variety has a distinct lime aroma instead of lemon. The foliage is lighter than in the species.

Lemon Balm Companion Plants

Parsley

Just like lemon balm, parsley grows best in full sun but benefits from partial afternoon shade in warmer climates. Parsley is a biennial which means it grows in one season, and after winter, it blooms, seeds, and dies, that’s why most gardeners grow it as an annual and discard the plant after the first season. For cooking, the best parsley to grow is flat-leaf Italian parsley. 

Sage

Sage is a multipurpose powerhouse with attractive foliage and pretty blooms in summer. This herb is most commonly grown for its flavor, but it also makes a tough perennial plant in the garden. Sage needs at least six hours of sunlight each day to have the best flavor. Zone 4-10

Dill 

Dill serves both humans and pollinators alike. Gardeners snip fresh dill for cooking while black swallowtail caterpillars feed on the feathery leaves. If you don’t cut it all and let it reach the flowering stage, its yellow umbels are excellent for attracting a variety of pollinators. Dill is usually grown as an annual.