Conradina verticillata aka Cumberland Rosemary

Conradina verticillata is a small shrub in the mint family. It is evergreen, which means it keeps its leaves. People call it Cumberland rosemary or Cumberland false rosemary. It comes from the Cumberland Plateau in Kentucky and Tennessee. There, it grows beside streams on sand and gravel. These banks flood in some seasons, then dry in summer. The US Fish and Wildlife Service lists this rare plant as threatened. NC State says rules ban sales across state lines.

Garden plants grow 1–2 feet (0.30–0.61 metres) tall and wide. Missouri Botanical Garden gives a usual height near 1.25–1.67 feet (0.38–0.51 metres). The shrub forms low clumps or mats of spreading branches. Stems trail across the soil and root at their nodes. These are the points where leaves join the stem. A cut across a stem shows a square or near-square shape. The bark is dark brown. The shaggy stems are reddish-brown. The plant keeps its leaves through winter, giving gardens year-round interest.

The stiff, dark green leaves look like small rosemary needles. They grow in pairs on opposite sides of the stem. Their edges are smooth. Each leaf joins the stem without a stalk. Leaves reach about 0.06 feet (0.02 metres) in length. They smell like rosemary and mint, most so when crushed. Sweet-smelling flowers open in May and June. Each flower has two lips. Its petals are lavender-pink with red spots. Flowers grow alone or in small groups along the stems. The fruits are small, dry nutlets.

Grow this shrub in full sun and soil that drains well. It also accepts some light shade. It suits sandy, acid soil, even soil with few nutrients. Its garden needs range from dry soil to soil with some moisture. Once plants take root, they resist drought and cope with dry ground. Sources place it in USDA hardiness zones 6–8. It has a short life but may sow itself in suitable conditions. Those seedlings can help keep a planting going over time. Gardeners can also raise new plants from seed.

Use it in rock gardens or native plant beds. It also suits areas where plants grow and spread on their own. Use it along stream edges where the soil drains well. Plant it in small groups or larger masses. Its fine leaves and spring flowers add texture to these plantings. NC State lists it as a choice for pollinator gardens. Neither NC State nor Missouri Botanical Garden reports major pest or disease problems. The leaves can replace rosemary as a cooking herb. Plants For A Future gives it a low food-use rating. That source lists no known hazards or uses as medicine.