I'll note right away that Russian sage belongs to the genus, Perovskia. This fact immediately distinguishes Russian sage from a number of plants with which you may be familiar -- plants that belong to the Salvia genus.
But even within the Salvia genus, we find quite a bit of variety. Garden sage (Salvia officinalis) is an herb, perhaps best known for its use in preparing stuffing for poultry dishes. But as Marie Iannotti observes, Salvia officinalis does have its ornamental uses. Indeed, 'Tricolor' sage (Salvia officinalis 'Tricolor') is as highly ornamental as its cultivar name suggests.
But when you see the name, Salvia, your first thought is probably not of the herb, as discussed by Amy Jeanroy. Instead, a flower comes to mind, right? Or rather, a number of flowers. Red salvia (Salvia splendens), an annual, is a popular bedding plant. Another flower not hardy where I live is Victoria Blue or "mealy-cup sage" (Salvia farinacea 'Victoria Blue').
Read article: Russian Sage Plants
Related resource: Perovskia
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