How to Grow Lemon Balm: A Toronto Master Gardeners Guide

Lemon Balm (Melissa officinalis). Lemon balm is a perennial herb hardy to Zone 5. Grown for its lemon-scented leaves, lemon balm can be used fresh in salads and vinegars or dried to make teas.

Cultivation: Lemon balm is easy to grow and tolerates a wide variety of conditions, but it does best in moist, well-drained soil with full sun or part shade. Sow seeds indoors six weeks before the last frost and they will germinate in 10 to 14 days. Plant seedlings outdoors in late spring, either into the ground or a container. Lemon balm can also be grown indoors on a sunny windowsill but the flavour will not be as intense. Lemon balm likes moist soils but good drainage is also important.

Leaves can be harvested at any time by taking a few leaves as needed. To encourage new growth, cut the entire plant down to five centimetres from the ground (so that just the first set of leaves remains) a couple of times a year, particularly after flowering. Dry the leaves in a cool dry place. (

Lemon balm has inconspicuous flowers that can set a great many seeds, so it can quickly start to overtake the garden. Prevent this by removing any flowers before the seeds set or seek out plants of the smaller variety Melissa officinalis ‘Compacta‘, which does not set seeds.

If the plant becomes too large, lift and divide the plants every three years or discard them and start with new seedlings or cuttings. (R

Lemon balm may suffer from mildew, which is best avoided by providing good air circulation around the plant. If detected, cut the plant back hard (close to ground level) to remove all affected parts of the plant. Lemon balm can develop root rot if it is overwatered.

A few of the more attractive varieties are ‘Variegata,’ which has dark green leaves and golden yellow markings along the margins, and ‘All Gold,’ a selection with yellow leaves best grown in partial shade.

Disclaimer: Toronto Master Gardeners does not advise or recommend herbs for medicinal or health use. Any information in the recommended resources should be regarded as being for educational purposes only and should not be considered as a recommendation or an endorsement of any medical or health treatment.

For more information:

Herb Society of America https://www.herbsociety.org/hsa-learn/hsa-publications/hsa-essential-guides.html

OMAFRA http://www.omafra.gov.on.ca/CropOp/en/herbs/culinary/lemba.html

Richters Herbs https://www.richters.com/Web_store/web_store.cgi?product=X1240&show=all&prodclass=&cart_id=7069590.21283

RHS Grow your own herbs: Lemon Balm https://www.rhs.org.uk/advice/grow-your-own/herbs/lemon-balm

University of Illinois Extension https://web.extension.illinois.edu/herbs/lemon-balm.cfmes

University of Wisconsin-Madison: Wisconsin  Horticulture Division of Extension https://hort.extension.wisc.edu/articles/lemon-balm-melissa-officinalis/

West Coast Seeds https://www.westcoastseeds.com/blogs/how-to-grow/grow-lemon-balm

Date revised: December 2021

Prepared by the Toronto Master Gardeners, these Gardening Guides provide introductory information on a variety of gardening topics.  Toronto Master Gardeners are part of a large, international volunteer community committed to providing the public with horticultural information, education and inspiration.  Our goal is to help Toronto residents use safe, effective, proven and sustainable horticultural practices to create gardens, landscapes and communities that are both vibrant and healthy.

Statement on Invasive Plants: When choosing plants, avoid invasive plants, which can spread quickly and dominate gardens.  Invasive plants are sold by nurseries, big box stores or even at community plant sales.  Invasives may already be present in your garden.  They can invade gardens by spreading from under a neighbour’s fence or may be transported by wildlife.  For beautiful, sustainable options to invasive plants, see the Ontario Invasive Plant Council’s “Grow Me Instead – Beautiful Non-Invasive Plants for your Garden” at https://www.ontarioinvasiveplants.ca/resources/grow-me-instead/before purchasing or accepting “gifts” of plants.

Statement on Home Remedies: The Toronto Master Gardeners do not recommend home remedies, as these have not been proven effective through scientific investigation, and may even damage other living organisms in the soil or plants in your garden.  There are other garden friendly options you can use.

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