Gentiana dahurica (syn. Gentiana gracilipes)
If you have never grown Gentians in your garden, well, you should. There are very few flowers in the Plant World that are "Gentian Blue," and, besides, they are just so beautiful. Gentiana dahurica is an easy one to grow and makes an ideal candidate for a first Gentian. The late summer/early fall flowers are true blue with white spotted throats and form from the leaf axis and from the tips of the leaves. These only grow to about eight inches tall, and if they are grown away from other plants that offer support, they tend to be lax and cover the ground. Either way, they are not a disappointment and, as a bonus, are long lived. Moist, well-drained soil in full sun to part shade in Zones 4-8. (Illustration by .By M.S. del., J.N.Fitch lith. [Public domain], via Wikimedia Commons). The illustration is lovely, but the blooms are blue, not purple.