Poliomintha incana aka Frosted Mint

Poliomintha incana is a shrub in the mint family, Lamiaceae. Its native range spans the southwestern and west-central United States. It extends south into northern Mexico. Kew lists it as a plant of subtropical climates. It can take the form of a shrub or subshrub. The RHS confirms its accepted name and family. It is not native to Britain or Ireland.

This plant forms a dense shrub with upright twigs. Virginia Tech gives its height as 4 feet [1.2 metres]. The close growth brings its small leaves and flowers together. Pale gray bark develops a scaly surface. Young twigs have a pale, silvery blue-green color. Fine hairs cover them, and their shape is somewhat four-angled. The bark and young stems thus have different surface textures. Both contribute to the plant’s pale appearance.

The evergreen leaves grow in opposite pairs along the stems. Each leaf is simple, rather than divided into leaflets. Leaf shapes range from oblong to narrow and strap-like. Some have the tapered outline described as lanceolate. Their edges are smooth, with no teeth or lobes. The tips are rounded, and the leaves lack stalks. Fine hairs cover both the upper and lower surfaces. These hairs accompany the foliage’s silvery blue-green color. The leaves share this pale color with the young twigs.

Flowers appear in spring and range from white to purple. They grow where the leaves meet the stems. Each of these small groups holds one to three flowers. A single flower reaches about one-third of an inch across. Virginia Tech describes the blooms as pea-like and strongly scented. Its account also identifies the species as monoecious. The fruit is dry rather than fleshy. At maturity, it separates into four nutlets. These small fruit sections contrast with the scented spring blooms.

The supplied records give more detail on appearance than garden care. They do not set out soil, light, or watering needs. They also give no hardiness zones or garden spread. No specific landscape use appears in these records. Nor do they document pests, diseases, or weed problems. They provide no evidence of edible parts or medicinal uses. They do not establish safety for people or pets.