Understanding the salvia spectrum

The genus Salvia contains roughly 900 species, and the heartbreak of salvia growing is that most gardeners discover too late that not all of them are hardy. The bedding salvia you bought in May — that electric-blue Salvia patens or the velvety Salvia 'Amistad' — will very likely die at the first proper frost. Meanwhile, the unshowy Salvia nemorosa you planted once five years ago has quietly returned every spring without fuss.

This is not a defect in your gardening. It is botany. Salvias come from wildly different climates — Mediterranean hillsides, Mexican highlands, Turkish scrubland, Brazilian cloud forest — and they retain their native tolerances. Your job is to sort them into three tiers: the reliably hardy perennials that need no coddling; the borderline types that survive most winters in southern England but not Yorkshire; and the tender beauties you must either treat as annuals or bring indoors before October.

Once you understand this spectrum, salvia growing becomes strategic rather than bewildering. You can plan for succession, for insurance cuttings, for indoor windowsill colour in February. The genus rewards attention with months of flower, hummingbird-magnet blooms, and foliage that ranges from felted silver to glossy green. But you must meet each species on its own terms.