Teucrium hircanicum, sold in the nursery trade as Purple Tails, is a clump-forming perennial native to the Caucasus and northern Iran. Upright stems carry dense whorls of deep purple flowers from midsummer into early fall, drawing sustained pollinator traffic from bees and hoverflies. The long display period and low maintenance demands make it a reliable choice for mixed borders and pollinator-focused plantings.
Plant in full sun with lean, sharply drained soil. It tolerates drought once established but declines in poorly drained or waterlogged ground, particularly over winter. Working coarse grit into heavy clay soils significantly improves long-term survival. Cut all stems to near ground level in early spring before new growth emerges. Clumps remain productive for several years before division is needed to restore vigor. The epithet hircanicum refers to Hyrcania, the ancient name for the Caspian region where the species originates.
Powdery mildew
White or grey powdery coating on leaves - usually starting on older growth in humid conditions or when nights cool.
Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.
Root rot
Plants wilt, yellow, and stunt even in moist soil; lower stems and roots turn brown, soft, and mushy and the plant may collapse. Most common in heavy, wet, or poorly drained ground.
Improve drainage and stop overwatering, and never plant too deep. Lift and destroy badly affected plants along with the soil around the roots. Grow in raised or free-draining beds to prevent it returning.