Lemon Balm
Other Common Names Include:
Melissa, dropsy plant, honey plant, cure all.
Latin Name: Melissa officinalis
Plant Family: Lamiaceae (Labiatae)
Close Relatives: Bergamot, mint, thyme
Uses and Markets: Culinary (e.g. flavouring, teas, candies), industrial (e.g. perfumes), medicinal (e.g. sleep disorders, digestive disorders).
Production Life Cycle in Ontario
Perennial
Hardiness Zone
4
Special Notes
Seeds germinate more successfully if they are not covered.
Propagation method
Most commonly by transplants from seeds (produces highest yields); also by direct seeding, root divisions and stem (stolon) cuttings.
Greenhouse Seeding/Propagation Dates
Early spring.
Field Seeding Date:
May
Field Transplanting Dates
Late spring.
In-row spacing
30-60 cm
Between row spacing
50-75 cm
Optimal Soil temperature at planting
In general, perennial crops can tolerate low soil temperatures at planting, but will establish more rapidly at soil temperatures >10°C.
Fertility
No current Ontario fertility recommendations exist. Research and recommendations from outside Ontario do not necessarily apply to Ontario growing conditions. In a study in Poland, highest herb yields were achieved with 90 to 120 kg/ha N per year. Click here for phosphorus and potassium application guidelines and for more information on specialty crop fertility.
Soil type
Moist, well-drained soils.
Soil pH
5.0-7.5
Special requirements for growth habit
Crowns should be mulched in the winter.
Optimal Temperature Range
15-30 °C
Temperature sensitivity
Freeze tolerant but mulching is recommended before first hard freeze.
Irrigation requirements
Irrigation required under normal Ontario conditions (very sensitive to moisture stress).
Days to harvest
60 days to first harvest.
Specialized equipment:
None
Harvest
Harvest Scheduling
Multiple harvests from the same planting. A single harvest is best during the first year and 2-3 harvests are recommended in the following years. Harvest before blooming. For dried leaf production, often grown as an annual or harvested in the first two years and then replanted.
Hand harvest or machine harvest
Hand harvest (fresh leaves); Machine harvest with a sickle bar or side bar cutter (dried leaves).
Quality parameters/grades
No established grades. Quality is determined by the market.
Additional Harvest Notes
Harvest during cooler parts of the day to reduce moisture loss and cooling costs. Remove field heat as soon as possible after harvest. Harvest by cutting off the top growth leaving 5 cm of stem for re-growth.
Post harvest
Special handling/curing
Avoid bruising leaves. For essential oil, steam distil fresh leaves as soon as possible after harvest. Dry leaves at 20-35 °C.
Storage Conditions
Relative humidity (RH): Low for dried products, high for fresh flowers and leaves (>80%).
Temperature: 0°C (herb)
Air Exchange: N/A
Duration: 7-14 days (fresh leaves); One or more years if properly stored (oil and dried products).
Specific pests observed on this crop in Ontario (observations based on limited experience with this crop)
Insects and Invertebrates: Four-lined plant bug (Poecilocapus lineatus)
Diseases:
Other Potential Pests: The following pests have not been observed on this crop in Ontario. However, they are either significant concerns for closely related plants in Ontario, or are reported on this crop in other production areas. This is not a comprehensive list of all potential pests. Not all of these pests will necessarily survive Ontario’s climate, but could potentially survive in a protected environment (e.g. greenhouse, storage facility).
Insects and Invertebrates: Whiteflies, aphids, mites
Diseases: Powdery mildew, root and crown rot, fungal leaf spots.
Comments
To date the following pests have been the most significant in Ontario: four-lined plant bug. Disease pressures can be reduced through proper site selection and by promoting good air movement through the canopy. This crop is in Crop Group 19: Herbs and Spices Group and subgroup 19A: Herb Subgroup. This crop group is being revised and may change in the near future. For more information on Crop Groups, refer to the Pest section. Always refer to product labels, and follow all directions specified on the label, before applying any pest control product. For more information, consult an OMAFRA specialist. For pest control products registered on this crop refer to OMAFRA Publication 838.
None
- McKeown, A.W., C.J. Bakker and J. Schooley. 1998-2002. Herb Demonstration Garden, University of Guelph Simcoe Research Station, unpublished.
- Westerveld S.M. and C.J. Bakker. 2007. The effect of composted poultry manure and hay mulch on yield of lemon balm. Vegetable and Non-Traditional Crops Research Report 2007, University of Guelph Simcoe Research Station.
- Westerveld, S., Elford, E., Filotas, M. and J. Todd. 2010-present. OMAFRA herb demonstration garden. OMAFRA Simcoe Resource Centre, unpublished.
- Bown, D. 1995. The Royal Horticultural Society Encyclopedia of Herbs and their Uses. BCA, Toronto.
- Davis, J.M. 1997. Lemon balm. North Carolina State University.
- Foster, S. and J.A. Duke. 2000. Eastern/Central Medicinal Plants and Herbs. Houghton Mifflin Company, New York.
- Halva, S, L.E. Craker. 1996. Manual for northern herb growers. HSMP Press, Amherst MA.
- Kordana, S., Mordalski, R. and R. Zalecki. 1997. Effect of amount of sown seeds, time of herb harvesting and fertilization on herb crop and quality of lemon balm. (Melissa officinalis L.). Herba Polonica 43: 135-144.
- Kowalchik, C. and W.H. Hylton. 1998. Rodale’s Illustrated Encyclopedia of Herbs. Rodale Press, Emmaus, PA.
- McHoy, P. and P. Westland. 1994. The Herb Bible: The Ultimate Herb Reference Book. New Burlington Books, London UK.
- McVicar, J. 1994. Jekka’s Complete Herb Book. Raincoast Books, Vancouver.
- Small, E. 2006. Culinary herbs, 2nd Edition. NRC Research Press, Ottawa.
- Turhan, H. and C. Onsekiz. Lemon balm, pp. 390-399. In: Peter, K.V. (ed.). Handbook of herbs and spices, CRC Press, New York.
