Plant in reliably moist or boggy soil, or in pots/pond baskets at the water’s edge, keeping the crown just above water. They prefer full sun but will tolerate light shade. Keep the soil consistently wet, and in winter either move pots indoors or treat as annuals outdoors, as they won’t survive frost.
Prune old or yellowing stems regularly to keep plants tidy and encourage new growth, and divide clumps every 2-3 years to maintain vigour. Fertilise in the growing season with a balanced liquid feed (in pots), or slow-release aquatic fertiliser tablets pushed into the soil near the roots to support strong foliage.