This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
A graceful Spiraea-like herbaceous perennial from North America. It grows 1-2 ft. high, has slender dark-red stems, three-parted leaves, and loose clusters of white and reddish flowers in June and July. G. stipulacea is somewhat similar, but has loose-shaped deeply cut leaves and white flowers. Both kinds flourish in ordinary garden soil, and like semi-shady spots. They may be increased by division.