Growing in the soil
Lavender is best planted between April and May as the soil is warming up. It thrives in any poor or moderately fertile, free-draining soils in full sun, and is ideal for chalky or alkaline soils.
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 and is suitable for coastal planting and gravel gardens.
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, up to 30% by volume, to improve the drainage, and some controlled release fertiliser granules.
Ensure that the compost is regularly watered in summer, but for improved cold tolerance, kept on the dry side during winter by standing in a cold greenhouse or in the rain shadow of walls.
Most lavender can be grown in pots, but it is ideal for tender types - H3 (half hardy) or H2 (tender), such as Lavendula canariensis, L. dentata var. dentata 'Royal Crown' AGM, L. lanata AGM or L. pinnata, which need to be brought undercover during winter and provided with light, well-ventilated conditions.