Lemon balm may be a common-or-garden plant, but it’s also a valuable source of essential oil, writes ethnobotanist Susanne Masters

I’m helping to revive and replant the ethnobotanical garden at the University of Kent. One of our tasks is to revamp the garden’s plant catalogue to make it interactive, as well as more useful for a range of disciplines.

One of the plants in the catalogue – lemon balm – stands outs as an ideal plant for people to engage with and learn about. One plant of lemon balm in a garden quickly turns into many, as it self-seeds readily in flowerbeds or even gaps between paving. It is a common but underappreciated garden plant, possibly because it is easy to grow – it is tolerant of a range of conditions, including drought, and isn’t affected by many pests and diseases.
Lemon balm has a scientific name – Melissa officinalis – that came to life with bees. Blooming plants attract scores of bees, which feed on the tiny white flowers, and the genus name Melissa is derived from the Greek word for bee. It has square stems and leaves in pairs, which are characteristic of the Lamiaceae (mint) plant family. These are easy features to look for without any equipment, making it a simple plant for botanical beginners to get to grips with. Lemon balm exudes a strong lemon scent when the leaves and stems are crushed, and this is a readily detectable feature for initiating discussion of phytochemistry: investigating compounds made by plants, what their function is in plants, and how they can be useful to people. Best of all, even a small scrap of stalk will readily root in a glass of water, making it a plant for garden visitors to take home and grow on a windowsill or in their own garden.
Lemon balm produces an essential oil that is one of the most expensive to buy; production costs are high because yields are low. Although the lemon scent can be replicated using cheaper citrus and lemongrass essential oils, pure lemon balm essential oil is valued for its properties in aromatherapy where it is considered to be uplifting and calming, and in skincare as an anti-inflammatory. Lemon balm is one of those plants with a long history of medicinal use. Small laboratory trials report antiviral, antioxidant and calmative properties. But the results are not good enough to turn it into a prescribed medication. Some folk remedies may never be wonder drugs. Perhaps lemon balm is best appreciated on a sunny morning as a cup of tea in hand while watching and listening to bees on its flowers, or at dusk with a few stems crushed underfoot to keep mosquitos at bay and a glass of lemon balm wine. Below, courtesy of Pauline Pearce from the National Guild of Wine and Beer Judges, who has won many awards with this particular recipe.

Lemon balm wine (ingredients for 1 gallon)

2 quarts lemon balm
2 large oranges large (juice and rind)
1lb sultanas
1 lemon (juice and rind)
1kg sugar
1 tsp nutrient
1 tsp tartaric
1 tsp pectic enzyme
Gervin or any general purpose wine yeast
Campden tablets

Strip the leaves from the stalks (discard the stalks) then wash leaves in cold water. Drain and put into a clean container and pour over 4 pints of boiling water, add one Campden tablet, stir, cover and leave for 48 hours.

Strain the liquor from the leaves (discard theleaves) into a sterilized bin, add rind (no pith) and juice of the oranges and lemon, the washed and chopped sultanas, acids, pectic enzyme, nutrient and yeast. Ferment on the pulp for four days, stirring twice daily, keep well covered.

Strain into jar, add sugar and stir, top up to shoulder with cold boiled water, fit air-lock and leave to ferment out. Rack in the usual way.

This wine can either be served dry as an aperitif, or sweeten to taste and drink as a social type wine.

Can be drunk within three months but improves with keeping for a further three months.

Susanne Masters is an ethnobotanist who writes for a number of magazines, and is doing PhD research on edible wild orchids in Turkey. This is the latest in a series of posts about the redevelopment of the ethnobotanical garden at the University of Kent.

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