Lavender in April: monthly care

Lavender thrives in full sun and demands excellent drainage, so choose the sunniest spot in your garden where water never sits. It performs best in sandy, chalky or loam soils with a neutral to alkaline pH; heavy clay is its enemy. If your soil is dense or moisture-retentive, dig in plenty of horticultural grit or sharp sand before planting—aim for at least a third by volume—to open up the structure and prevent root rot. Plant lavender in April, May or September when the soil is workable and temperatures are mild. Container-grown plants can go in at any of these times, but spring planting gives them a full season to establish before winter. Dig a hole slightly larger than the root ball, set the plant at the same depth it sat in its pot, and firm the soil gently around the roots. Space plants 40 cm apart centre to centre; this allows air to circulate freely and reduces the risk of fungal disease as the plants mature and fill out. Water thoroughly immediately after planting to settle the soil, then water every few days for the first fortnight if conditions are dry. After that, lavender needs very little irrigation; overwatering is a common mistake. Avoid adding organic matter such as compost or manure at planting time—lavender evolved on poor, stony hillsides and too much fertility encourages soft, leggy growth at the expense of flowers and fragrance. A light mulch of gravel or grit around the base helps suppress weeds, reflects heat, and keeps the neck of the plant dry, which is especially useful on heavier soils.

Lavender needs pruning twice a year to stay compact, floriferous and long-lived. Without it, plants become woody, bare at the base and prone to splitting open in wind or snow. The first prune is a light tidy in August, immediately after the main flowering flush. Use clean, sharp secateurs or garden shears to cut off all the spent flower stems, taking them back to just above the first set of leaves below the faded blooms. This deadheading prevents the plant wasting energy on seed and often encourages a modest second flush of flowers in early autumn. The main structural prune happens in March or April, just as new green shoots begin to appear at the base of the old stems. Cut back all the previous year's growth by about one-third to one-half, shaping the plant into a neat, rounded mound. Always cut into the green, leafy growth—never back into thick, bare brown wood, because lavender rarely regenerates from old stems and you risk killing whole branches or even the entire plant. If you're uncertain, err on the side of caution and take less off; you can always prune again next year. Use sharp bypass secateurs for precision or hedging shears for larger plantings and long hedges. Work your way around the plant evenly to maintain a balanced shape. If your lavender has become very leggy or woody, it's usually better to replace it than attempt drastic renovation. Well-pruned lavender will remain productive and attractive for ten to fifteen years.