Astilbe grow in clumps and benefit from being divided every four years or so. The flowers bloom for about four to six weeks in hues that span the spectrum from white, pink and red, to raspberry or purple. Individual blooms are small and densely arranged in fluffy sprays up to six inches long or more at the ends of tall stems. Depending on the variety, blooms may be stiffly upright or airily open and plume-like. Some varieties even have a subtle scent. There are early bloomers (June), mid-season bloomers (July) and late bloomers (September), which makes them a perfect compliment to the seasonal variety in the Conservatory Garden.

Astilbe does have an interesting history of cultivation. A botanist from Ronsdorf, Germany, George Arends, is responsible for introducing the majority of the Astilbe cultivars, many of which bear his name. Most of the species and varieties Arends bred were originally from Asia. Interestingly, Arends seemed to have passed over the only American representative, A. biternata. In any case, he developed so many variations that it is almost useless to try and list them all, not to mention tedious to the point of being obsessive. Due to the fact that the development of these colorful woodland wonders involved so many parents, the distinction among them is largely lost.

But, it is this variety that makes Astilbe such a valuable component of the Conservatory Garden. The feathery blooms of the fern-like flower can combine with any number of the more prominent blooms to create a richly-colored tableau that lasts from June until early September.