This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
This is a genus of hardy herbaceous plants from North America. Without having any very strong claim to be considered beautiful, they have a certain distinction and elegance in their appearance that renders them valuable for certain ornamental purposes. They may be introduced among shrubs with very good effect, and they may be planted in open woods where their robust hardy nature will enable them to establish themselves when less vigorous plants would succumb before the encroachments of the native vegetation. Any ordinary good soil suits them well, and they are easily propagated by division or seeds in spring.
Amsonia angustifolia grows about 2 or 3 feet high, with hairy stems and lanceolate leaves clothing them throughout. The flowers are produced in small panicles in the axils of the upper leaves, are light blue, and appear in July and August.
Amsonia latifolia is about the same in stature as the last, but the stems are usually destitute of hairs, and the leaves more broadly lanceolate. Flowers blue in the same manner, but the panicles rather fewer flowered, and about the same time.
Amsonia salicifolia has hairless stems, and very narrow lanceolate leaves attenuated at each end. The flowers are numerous in small panicles in the axils of the upper leaves. They are blue, and appear about the same time as the others. W. S.