French Tarragon, True Tarragon
Several species are valuable for interesting leaf patterns and silvery gray or white aromatic foliage (flowers are generally insignificant). Most kinds are excellent in mixed borders, where their white or silvery leaves soften harsh reds and oranges and blend beautifully with blues, lavenders, and pinks. Provide good drainage. Cut nonwoody-stemmed perennials to ground in late fall to rejuvenate; prune back woody perennials and shrubs (into older wood if necessary) before first flush of spring growth. Divide perennials in spring or fall; propagate shrubs by cuttings.
There are two common forms of this plant, which is native to central and eastern Europe and southern Russia. French tarragon (may be labeled ‘Sativa’) is a sprawling, largely flowerless plant with shiny dark green, aromatic, flavorful leaves. Slowly spreads by creeping rhizomes, the stems becoming slightly woody and the whole plant remaining less than 2 ft. tall. Makes an attractive container subject.
Russian tarragon (may be labeled ‘Inodorus’) is a less desirable plant, lacking the characteristic flavor and aroma of true tarragon; it has upright, branching growth to about 3 ft. and small white flowers. Any seeds you find for sale will be for this culinarily inferior Russian tarragon.
Cut sprigs in early summer for seasoning vinegar. Use fresh or dried leaves to season salads and cooked dishes. Plants in all zones die to the ground in winter. Divide every 3 or 4 years to keep vigorous. Propagate by divisions or cuttings. Provide moderate to regular water, letting soil dry between waterings.