Classifying Salvia is a complicated business as there are so many different types, but growing them isn't.
Sun or light shade, most soils as long as they are not too wet, bee-friendly and scented leaves. Once they finish flowering, cut the whole plant down to a couple of inches and you should be rewarded with a second flush of blooms (care is different for woody-stemmed varieties in yesterday's post - eg Hot Lips).
Those pictured are all in 2 or 3 litre pots at £5.99. Click on images to enlarge. Other Salvias available in other pot sizes - details to come!