Lavender (Lavandula) is an easy to grow, evergreen shrub that produces masses of beautifully scented flowers above green or silvery-grey foliage. This drought-tolerant plant thrives in a sunny border, container or herb garden.
Cultivation notes
Growing in the soil
Lavender is best planted between April and May. It thrives in poor or moderately fertile, free-draining alkaline soils in full sun.
On heavier soils, like clay and clay loam, lavender tends to be fairly short-lived, becoming woody at the base. To prolong the life of your lavender on heavier soil, add organic matter and gravel to improve the drainage and plant on a mound. If growing as a hedge, plant on a ridge to keep the base of the plants out of wet soil.
Space plants 90cm (3ft) apart, or if growing a hedge, 30cm (1ft) apart or, 45cm (18in) for larger cultivars.
Once established, lavender is fairly drought-tolerant.
Growing in pots
Lavender can be grown in large pots, 30-40cm (1ft-16in) diameter, using a multipurpose or loam-based compost such as John Innes No 3, with some extra coarse grit to improve the drainage, and some controlled release fertiliser granules.
Ensure that the compost is regularly watered in summer, but kept on the dry side during winter.
Most lavender can be grown in pots, but it is ideal for tender types, such as Lavendula canariensis or L. pinnata, which need to be brought undercover during winter.
Pruning
Lavenders should be pruned every year to keep them compact. On established plants use secateurs to remove flower stalks and about 2.5cm (1in) of the current year’s growth, making sure that some green growth remains. At Wisley, pruning is undertaken in late summer after flowering, although spring pruning is sometimes recommended in books. Lavender does not break readily from old wood and neglected specimens are best replaced.
Lavender pruning with secateurs
Lavender pruning with shears
Old woody lavender in need of replacing