Salvia leucantha aka Mexican Bush Sage

Salvia leucantha, or Mexican bush sage, belongs to the mint family. It comes from Mexico and Central America. It grows in pine forests and seasonally dry tropical regions. This bushy subshrub lives for years where winters stay mild. Gardeners also grow it as an annual in colder places. Its leaves can stay green through winter in warm conditions.

Garden plants reach about 2–4 feet [0.6–1.2 metres] tall. Some reach 5 feet [1.5 metres], while Florida reports shorter plants. They spread about 2–3.3 feet [0.6–1 metre] across. Many stems form a clump with upright and arching growth. Fine hairs cover the grey stems, which have square cross-sections. The narrow, lance-shaped leaves feel soft to the touch. Their upper sides look grey-green, with pale or white undersides. The leaves have toothed edges and pinnate veins.

The flowers form long spikes above the leafy stems. Small white tubes emerge from soft, hairy purple calyces. The white flowers fade before their purple bases do. This gives the spikes colour for a longer time. Flowering starts in late summer and continues through autumn. Chicago lists blooms from September through December. The season lasts longer in warm zones. Hummingbirds and butterflies visit the flowers for food. The small brown fruit has four sections called a schizocarp. Each section separates into a nutlet with one seed.

Give this sage full sun and soil that drains well. Afternoon shade suits sites with strong summer heat. It accepts sand, loam, or clay, and varied soil pH. Rich soil and regular water help keep growth dense. Established plants cope with some drought, but prefer even moisture. Keep the roots clear of excess wet in winter. Sources place it in USDA zones 7–10 or 7–11. The RHS rates it H2 for UK conditions. Freezing weather can kill stems, and severe winters may kill plants. Grow it under glass where frost protection is needed.

Use it in borders, beds, containers, or groups of plants. Its late flowers suit butterfly gardens and informal planting. Cut flower stems last several days in arrangements. Deer and rabbits tend to leave it alone. Care needs are low, and serious pest trouble is uncommon. Whiteflies, aphids, mealybugs, and spider mites can still occur. Possible diseases include rust, mildew, leaf spot, wilt, and rots. Honey fungus is a rare risk. PFAF lists flowers and leaves as edible parts, but gives edibility zero. It does not describe this plant as a usual culinary sage. PFAF reports no known hazards, rather than proven safety. It notes medicinal claims but gives no clear use details.