Isatis tinctora (Woad) 9 cm Pot

Growth habit & appearance: A robust biennial forming a dense rosette of glaucous blue-green leaves in its first year, followed by tall, branching stems that carry clouds of bright yellow flowers in the second season. The foliage has a distinctive waxy bloom, and the deep taproot is the traditional source of its famed blue dye. Plants grown at our nursery in Co. Clare are raised from seed and establish reliably in Irish soils.

Growing conditions: Thrives in full sun and performs well in most free-draining Irish garden soils, including limestone-rich ground. As a hardy biennial, it overwinters outdoors without protection. In Ireland it benefits from an open, sunny aspect to prevent legginess and to maximise pigment development in the root. Remove flower heads if you wish to avoid prolific self-seeding, which is common in favourable conditions.

Traditional & herbal uses: Modern herbal interest focuses on its use for upper respiratory discomfort, throat irritation and inflammatory skin presentations. Extracts of the leaf and root are widely explored in contemporary herbal formulations, particularly in East Asian herbal traditions, where the plant remains part of ongoing clinical research.

Maintenance & harvesting: Keep beds weed-free during the first year so the taproot can fully develop. Plants require little intervention other than removing seed heads to control spread. Roots are traditionally lifted at the end of the first year for dye production, but leaves may also be taken periodically. Cut back spent growth after flowering and allow selected plants to set seed only if you plan to collect for re-sowing.