Common myrtle

Identification and origin

Myrtus communis belongs to the myrtle family, Myrtaceae, which also includes eucalyptus. It is native to southern Europe, North Africa, and southwestern Asia: it grows from the Iberian Peninsula, the Balearic Islands, and Macaronesia to Greece, Türkiye, the Middle East, and Iran, and east as far as Afghanistan and Pakistan, as well as in Eritrea, Ethiopia, and Yemen. It has become naturalized in places such as California, Texas, the Caribbean, and South Africa.

It is an evergreen shrub or small tree with an upright, bushy habit that slowly forms a rounded mound. In cultivation it usually reaches 5–6 ft tall and wide, and can grow to 8–13 ft after ten to twenty years. Its growth rate is medium.

The opposite, simple, leathery leaves are lance-shaped to oval, 1–3 in long, with smooth edges and no hairs. Glossy dark green above and paler below, they are dotted with translucent spots and give off a pleasant fragrance when crushed. The stems, by contrast, are not aromatic.

The fragrant, star-shaped white flowers are about 1 in across and carry a tuft of many stamens with yellow anthers. They open in summer and into fall, and a long, warm summer is needed for good flowering. They are followed by purplish-black to bluish-black berries the size of a pea, each holding up to about thirty seeds. Edible but not very flavorful, they can be used to make a liqueur. The bark, dark brown to cinnamon colored, becomes furrowed, thickens, and peels with age.

Long associated with love, myrtle traditionally appears in British wedding bouquets. Its dried leaves, flowers, and fruit are used to flavor food, the leaves can stand in for bay leaves, and oils from the bark, flowers, and leaves go into skin care products. In the garden it makes hedges, screens, and handsome specimens; bees visit the flowers and birds eat the berries. Dwarf or compact cultivars such as ‘Tarentina’, ‘Compacta’, and ‘Microphylla’ suit containers well, and ‘Leucocarpa’ has white berries.

Light

Common myrtle wants full sun and accepts light partial shade. In the ground, give it a south- or west-facing spot sheltered from cold, drying winds. In a pot it also enjoys sun, but during very hot summers a partly shaded spot suits it better. If it overwinters indoors, place it at a very bright south-facing window or add a grow light. It does poorly in deep shade.

Watering

Once established in the ground, it tolerates heat and some drought, but it dislikes standing water: good drainage prevents root rot. In a pot, the root ball should stay slightly moist at all times, never soggy, because drying out completely can kill it very quickly. Water as soon as the surface of the mix starts to dry, until water runs from the drainage holes, then empty the saucer. Watch the mix rather than following a calendar: a pot in full sun in midsummer drinks far more than one wintering in a cool room. Myrtle does not tolerate lime well, so rainwater is best.

Potting mix

In the ground it adapts to chalky, loamy, sandy, or clay soils, whether acidic, neutral, or alkaline, as long as they stay moist and drain well; it appreciates soil enriched with compost. Good drainage is essential to prevent root rot. In a container, use a lime-free, well-draining mix; for bonsai, peat or kanuma is added to the usual blend.

Temperature

Myrtle is a plant for mild climates. In the ground it tolerates frosts of 14–23 °F in a sheltered spot, but late frosts damage young spring growth. In cold regions, grow it in a container and bring it under cover before frost. It then spends the winter in a cool, bright room at around 50 °F. A warmer room with dry air and low light encourages pests.

Repotting

In a container, repot young plants every two to three years and older ones every three to five years, using fresh lime-free mix. Slightly crowded roots encourage flowering, so there is no need to choose a much larger pot.

Pruning

Myrtle branches very well and takes pruning, so it can be trained as a hedge, a screen, or a bonsai. To keep a compact shape, let young shoots grow six to eight pairs of leaves, then cut them back, leaving at least one pair of leaves on each twig to encourage new buds. Prune mainly after flowering so you can enjoy the blooms, and seal large wounds with cut paste.

Propagation

It is propagated from seed or cuttings. Semi-ripe cuttings taken in spring or summer give the best results, and air layering also works. Seeds are collected from ripe berries.

Common problems

In the garden, myrtle is generally pest-free and very resistant to honey fungus, which only rarely affects it. In hot, dry weather, however, scale, spider mites, and thrips can damage the foliage. Indoors, especially in winter in a warm room with dry air and low light, scale, mealybugs, and whiteflies readily take hold: treat with a suitable product and, above all, correct the growing conditions.

Remember that a symptom can have several causes: before treating, check watering, water quality, light, and the temperature of the spot.

Toxicity

Common myrtle does not appear among the toxic plants listed by veterinary references for dogs and cats: no toxicity is reported, and its berries are edible. Do not confuse it with periwinkle, sometimes called “running myrtle,” which is toxic to pets.