If Hidcote is the lavender your grandmother grew, Phenomenal is the Gen Z equivalent. It is a Lavandin — the same type as Grosso — but more compact, with darker flowers and, crucially, winter foliage that looks, well, phenomenal. That last point matters more than it sounds. Lavender is evergreen, but most varieties look a bit tired after a hard winter. Phenomenal's silver foliage stays dense and bright right through to spring, which earns its place in any border that you want to look decent all year round.

It flowers earlier than the older Lavandins, sometimes starting in late May in sheltered southern gardens, and if you deadhead the first flush it will often produce a second round later in summer. The colour is a deeper violet-purple than Grosso's softer blue, held on long stems that are excellent for cutting. It is fully hardy throughout the UK and has good resistance to the root and foliage diseases that can trouble lavenders in wetter areas on heavier soils. 

A Sport from Grosso

Phenomenal appeared in 2007 as a chance mutation — a sport — in a crop of Grosso lavender at Peace Tree Farm in Pennsylvania. The American grower Lloyd Traven noticed that among 30,000 field cuttings that had all but died in a brutal summer, a handful were not only alive but thriving. He took cuttings, grew them on, and watched them for several years. They were more compact than Grosso, kept their foliage better through winter, and shrugged off heat, humidity and cold that killed other varieties around them. He registered the plant for Plant Breeder's Rights (a bit like copyright) in 2012 and introduced it commercially in 2013. It was named one of the top 25 new perennials of that year by Better Homes & Gardens, and it has been gaining ground ever since — quite literally, on lavender farms and in gardens across Europe and North America.

• Height: 60–75cm (24–30in)
• Spread: 60–90cm