For optimal growth, plant Astilbe simplicifolia 'Hennie Graafland' in a shaded area with rich, consistently moist soil. Apply a layer of mulch to conserve moisture and minimize weed growth. Water deeply and regularly, especially during dry spells, to keep the soil evenly moist. Remove faded flowers to maintain a neat appearance and prune back foliage in late autumn. Divide the plant every few years in spring to rejuvenate and encourage robust blooms.