By Gary Wade
University of Georgia
Amethyst Falls wisteria (Wisteria frutescens 'Amethyst Falls'), is an improved cultivar of our native American wisteria. Plant this vine and you'll be pleasantly surprised at its less aggressive nature.
Yes, it will climb 20 to 30 feet. But it's less vigorous, less invasive and much easier to manage than its Asian relatives. Amethyst Falls is hardy from zones 5 to 9. It grows well in full sun to partial shade.
Early bloomerAnd while the Asian types may take 10 years or more to begin flowering, Amethyst Falls wisteria starts at one year old.
It flowers on new growth about two weeks later than the Asian types. That's late April to early May in Athens, Ga. Late-winter frosts seldom affect flowering. And if you lightly trim it after it flowers, it will produce a second flush of blooms in the summer.
Some people consider this vine a dwarf wisteria. Amethyst Falls has smaller leaves and flowers than the Asian types. The flowers are fragrant, lavender-blue and borne in 2- to 4-inch-long racemes that cascade from the foliage like a waterfall -- hence the name "Amethyst Falls."
Deer and drought tolerance are other outstanding attributes that earned Amethyst Falls Wisteria a Georgia Gold Medal in 2006. It's a perfect choice for pergolas, trellises or fences.
A tree?It can be trained as a freestanding tree form, too. Just tie it to a sturdy stake 5 to 6 feet tall and prune the top to encourage branching. Once a treelike canopy forms and the trunk becomes sturdy enough to stand alone, you can remove the supporting stake. This process is somewhat labor-intensive, but the wisteria tree provides an unusual accent to the landscape.
Prune an Amethyst Falls wisteria in late winter, if necessary, to shape the plant and remove undesirable growth. Then trim it lightly again after the first flush of blooms to encourage branching and more blooms.
A late-winter application of a complete fertilizer, such as 16-4-8, should be plenty for the year.
Amethyst Falls is easy to grow and maintain, and it offers terrific seasonal beauty in your landscape. It's everything you'd expect a Georgia Gold Medal winner to be.
(Gary Wade is a Cooperative Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.)