Lavandula angustifolia
Plate from Flore médicale, Paris, 1833–1835. Biodiversity Heritage Library, no known copyright restrictions.
Loves sun and dry, poor soil — the harder its life, the more fragrant the buds.
Plant in the sunniest, best-drained spot you have. Prune after flowering to keep it from going woody.
Use buds sparingly — a small pinch is plenty, as too much turns soapy. Lovely blended with chamomile before bed.