Slender deutzia grows wild in the forests of central and southern Japan, where its arching, brown stems weave naturally through woodland understory. The species epithet gracilis — Latin for slender — describes the plant precisely: stems are fine and spreading, leaves narrow and lanceolate, buds pinhead-small. In bloom, typically from late April into May, the shrub is smothered with narrow clusters of white, bell to star-shaped flowers that overwhelm the foliage entirely. The cultivar 'Nikko' has won both the Royal Horticultural Society's Award of Garden Merit and the Pennsylvania Horticultural Society's Gold Medal Award, and has earned them.

Mature plants run 2 to 5 feet tall with a rounded, spreading habit that works equally well as a foundation planting, low hedge, or woodland edge specimen. The plant tolerates adversity with unusual generosity — transplanting, cold, pollution, and drought once established all earn a shrug. Annual pruning immediately after flowering keeps the arching stems from becoming congested and ensures the following season's bloom is equally generous. In the cultivar 'Nikko', a bonus burgundy fall color extends the season further.