Choose a sunny position in well-drained, fertile soil that doesn’t get waterlogged in winter. Water freely while it’s actively growing in spring and summer, but once established it copes well with drier conditions. Avoid disturbing it unnecessarily, as this plant dislikes root disturbance, so choose a permanent spot from the start if possible.
Cut the stems back to ground level in late autumn or early winter, ideally wearing gloves as the sap can cause skin irritation. Every few years, divide congested clumps in spring or autumn to keep plants healthy and flowering well. Mulching in spring can help conserve soil moisture and suppress weeds.