Sage Leaves generally relates to Common Sage or Garden Sage, Salvia officinalis.
Sage's leaves are quite large, thin and oval-shaped. The leaves are grey-green, rough and downy on the top of the leaves, while the underside is deeply veined and filigreed. Purple sage is slightly less strongly flavoured than common sage, but a gorgeous deep purple colour.
Sage is highly aromatic. Sage is very pungent with a flavour that is herbaceous, savoury and astringent. Sage has a very direct astringency which some people do not like. Like some other herbs, e.g. bay leaves, drying gives a stronger sage than the fresh one.
From the garden, sage leaves are fine, but dried ones can be woody. So commercially, less woody forms may be used like Salvia triloba.
Sage is valuable for the cook as it cuts down the richness and fattiness of meats, so works very well with pork, hence its used in sausages and in stuffing mixes. Sage and onion stuffing is a mainstay of British roast chicken dishes and American Thanksgiving turkey, while saltimbocca use fresh sage leaves. Generally, sage combines well with apples, pulses, onions and tomatoes, or blended into bay, garlic, ginger, marjoram, paprika, parsley and thyme.