Lavender has enchanted humankind for millennia with its medicinal and aromatic properties. This no-fuss herb also beautifies your garden all year round. The delicate, old-fashioned and grandmotherly scent most associated with lavender is still very sought after in certain cultivars. But the best-known lavenders in South Africa, the French (Lavandula dentata) and Spanish (Lavandula stoechas) varieties, as well as Lavandula intermedia 'Margaret Roberts', have a higher camphor content and a sharper, more powerful fragrance. Whatever they may lack in delicacy, however, they make up for in hardiness, thriving in our climate and flowering throughout the year. The sweetly-scented varieties angustifolias and other intermedia are less hardy and only flower during the summer months. One can now find Lavandula intermedia 'Grosso,' cultivated largely for its aromatic oil, at garden centres from time to time, while many Angustifolia cultivars are available from specialist nurseries or cultivators. The fern-leaf lavender, Lavandula pterostoechas 'Blue Canaries', has a herby scent, but certainly doesn't smell like lavender. It looks beautiful in a massed display, however, and will reward you with the cloud of purple-blue flowers throughout the year. The foliage lavender, Lavandula allardii 'African Pride', meanwhile, is used primarily for low hedging and can reach heights of up to two metres, with thick, woody stems. Growing tips Soil: Lavenders like good drainage, so clay soil should be mixed with river sand and compost. Make sure that other soil types are well prepared with compost and never allow water to pool around the plants.
Leaves: Most lavender varieties have greyish foliage, but French lavender has green, fittingly dentate leaves.
Flowers: The French lavender, 'Margaret Roberts' and the fern-leaf lavender flower throughout the year, while other intermedia cultivars and the Angustifolia varieties only flower in summer. Spanish lavender flowers in late winter, spring and autumn. The intermedia and Angustifolia lavenders have long stems tipped with small, tightly packed flowers; French lavenders produce plump, medium-sized flowers, while Spanish lavender has thick, fleshy flowers with prominent crowns in shades from white through pink to purple. The fleshy parts of the flowers often have minute 'flowers' of their own. Feeding: Lavenders will flower even without food, but a handful of organic compost in early spring will be richly rewarded with brilliant blooms.
Maintenance: Lavenders are somewhat drought resistant, but will grow and flower better if you water the plants every other day during the summer. Cut off dead flowers regularly, or the plant will stop blooming as generously, and flower stems will become shorter. Lavender bushes that are cut back by a third every year and neatly shaped will look better for longer, but old plants eventually become woody, and no new growth will form on the old, woody stems. Replace your lavenders when they start dying off in patches, or if the stems are thick and woody.
Good companions: Lavenders will happily live with any other plants that like full sun and good drainage.
Pest and diseases: Under warm, damp conditions, a mealybug may appear, but this can be treated with any suitable pesticide. The biggest problem with lavenders, however, is that they're prone to dying off in patches, after which the entire plant dies. Spanish lavender partially dies off without adequate air circulation, while entire plants will swiftly perish without proper drainage. Address that problem proactively by supplementing the soil with sand and compost before you start planting. According to some sources, the patchy die-off in lavenders is the result of a fungus which attacks the plant's roots and leaves. This spreads through tiny spores that need to be treated with an all-purpose preparation such as Fungicide. The fungus won't be visible, but parts of the plant and in extreme cases, the entire plant will wilt and die. The fungus causes root rot and flourishes in compacted soil.