The genus of salvia contains over 900 species. They are members of the `lamiaceae’ or mint family or lip flowering. Traditionally sage as it is also known was used as herbs for its beneficial and medicinal properties.
Over the years many flowering varieties from Mexico, Central and South America and Southern states of the USA have become popular with a lot of European countries such as the UK because of their considerable long flowering period and diversity in flowers and leaf shapes.
They are also very good pollinators which are regularly visited by bees, bumblebees, moths and humming birds in tropical climates.
Many experts / growers place salvias into 3 categories which are listed below, determined mainly by their winter hardiness.
Hardy Herbaceous (up to -22°C)
We can generally say these are regarded as fully hardy salvias, variety’s such as salvia nemorosa, s. verticillate, s. pratensis s. sylvestris.
Hardy bushy salvia’s (up to -8 ° C to -12 ° C)
This group contains some of the most popular varieties such as microphylla, greggii, and x jamensis. They bloom in full sun from May to November. These survive most reasonable winters in England. Always add some leaf mould round the base during hard winters to give extra protection. A slight pruning in late summer helps stimulate further flowering until the frosts. Hybrids such as involucrate, guaranitica and uliginosa are also hardy in some areas of the country.
Semi-winter hardy and frost sensitive salvia`s (0 °C to -8 °C)
This group contains a lot of the Latin American and Californian varieties. These will need protection over the winter in greenhouses or cold frames keeping the frosts out. Take some cuttings as a precautionary measure and keep frost free. A lot of the new love and wishes range are not hardy and will need protection.