Otherwise, this is a carefree plant. Keep them mulched to provide a cool root zone and water when weather is dry. I seldom fertilize mine. I ll give them some Holly Tone which one of the commercial fertilizers formulated for acid loving plants. Most plants are container grown these days, so transplant shock is not much of an issue, although I think they are best planted in spring.
New growth is reddish and almost as lovely as the flowers.
Another, White Water is a low growing form with bright yellow new growth. Others have been bred to stay small and are suitable for the rock garden. There are at least two cultivars with variegated leaves. I have Variegata , which has a green and white leaf and white flowers, really quite lovely. Another is Flaming Silver , which sounds exceptionally neat.