Heleniums are versatile plants that love plenty of sunshine and moist soil. They rarely suffer from pests or diseases, however young plants do need to be protected from slug attack. To encourage the plant to repeat flower deadhead back to side shoots that have flower buds emerging. Cut back by half after flowering to help prevent mildew. Cut down to the ground in late winter. Every two or three years divide the plants in spring to keep them in top condition. When replanting add loads of well-rotted organic matter to the soil to feed them and keep them moist.