Trim English lavender to keep it neat and also delay flowering time – ideal if you want to prolong your display of lavender right into summer.
Normally English lavenders (Lavandula angustifolia), like old favourites 'Munstead' and 'Hidcote' are pruned in late August to keep it neat for winter. But a second haircut now promotes lots of new growth, filling it out nicely ready for summer, and delays flowering a little: combine with earlier-flowering French lavenders to extend your lavender season.
Don't be too brutal – save that for the late summer prune, when you can cut back quite hard as long as you can still see some grey tufty shoots below the point of cutting. The late spring prune is more of a light haircut, just snipping off the top few centimetres of new growth without cutting into old wood at all. The plant responds by redoubling its efforts to produce a nice hummock of soft grey foliage, topped with a forest of those delightfully scented mauve flowers from midsummer onwards.
Beware, though - this regime won't work with French lavender, easily recognisable from the tufty flag-like petals atop each flower spike. These are less hardy and flower earlier, so just trim very gently in late June.