Perennial Plant Profile: Amsonia

A friend of mine acquired a plant that was unfamiliar to her. She did not have a clue what it was called. She just knew that she really liked its appearance and the fact that it was such an easy-care plant. Turns out her plant is an amsonia.

You might not be familiar with the amsonia either; however, it could quickly become one of your favorite plants once you have incorporated it into your landscape. This is a perennial that you can plant and almost forget. It is not too picky about its soil, adapting to almost any type of well-draining soil. Watering is not much of an issue; although, you will not want to let it dry out during the summer months. It grows relatively slowly, eventually forming a 2-3-foot-wide clump that tends to stay put and really does not need dividing. (You can divide your amsonia if you want plants for other areas in your landscape, or you can just allow it to self-seed and dig up the new plants.) The clumps are also so dense that weeds are not an issue. You really do not have to spend any time pruning it either. (Amsonias grown in less than full sun can get floppy and need staking; however, you can cut these back hard after they bloom to encourage a bushier growth and eliminate the need for staking.)

The foliage of amsonia has lance-shaped, finely-textured leaves. (Some varieties remind me of the leaves on an asparagus fern.) In late spring or early summer, clusters of pale-blue star-shaped flowers are produced, which last about four weeks. Do not cut back your amsonia after it blooms if you want to enjoy its fall color. The leaves turn a bright golden-yellow in the fall, which makes it also a great addition to the fall garden.

Amsonia is hardy in Zones 3-9. (Mulch well in more northern climates.) Most species grow 2-3-feet-tall. They are great in a meadow garden. You can also make a nice hedge using several amsonias. It also works well with such other perennials as coneflowers and rudbeckias.

Varieties of interest:
Arkansas amsonia (A. hubrectii): This variety has feathery foliage and pale-blue flowers.
Willow blue star (A. tabernaemontana): This is probably the variety that you will most often find in nurseries and greenhouses. It has broader leaves and darker blue flowers than the Arkansas amsonia. It also does not produce the bright yellow color in the fall.

References:

Hodgson, Larry. Perennials for Every Purpose. Emmaus, PA: Rodale Organic Living Books, 2003.

Rogers, Marilyn, ed. Beautiful Perennials. Des Moines, IA: Meredith Corporation, 2006.