Q: I love wisteria but am having a hard time with it here in Minnesota. It’s not making much progress up my wooden arbor. — James A. Reider, White Bear Lake, Minn.
A: Your wisteria is root-hardy, but all the top growth it puts on each year is killed by severe winter temperatures. No wonder it’s not getting anywhere on your arbor. The two most common wisterias are W. sinensis and W. floribunda; the latter is a bit hardier. Its flower clusters are longer and more fragrant, but if your plant has never flowered, the best way to tell which one you have is the manner in which it twines: right to left for W. floribunda, left to right for W. sinensis. If you find you are growing the less hardy species, you might give W. floribunda a whirl. You might also consider wrapping the new growth in burlap for a little extra protection. If swaddling it is out of the question, you may have to settle on another vine. Incidentally, I hope your arbor is made of strong, thick timber: wisteria’s anacondalike stems have brought down many a finely wrought Victorian porch and gazebo.
Americans seem to have a strong distrust of vines; we grow them much less than other garden plants. It probably comes from a Freudian hang-up about lush, twining, probing shoots and tendrils or, more likely, our fear of the self-important, strangling imported thugs we see taking over in nature — porcelain berry, Hall’s honeysuckle, and kudzu. I’d like to see increased use of vines and more imaginative ways of growing them. Why not plant different vines at the base of your arbor and let them fight it out? You’ll have more interesting foliage shapes and textures and more flowers over a longer period of time. And, should some prove not as hardy or as vigorous as others, you won’t be left with a bare arbor. Why not be Darwinian and let the tough Minnesota winters weed out the weaklings?
Try trumpet creeper — the plain red species (Campsis radicans), not the named varieties that are less hardy — for its deep-green foliage and wonderful junglelike red flowers in late summer. It’s vigorous and can climb up a wooden arbor unassisted. Native Dutchman’s pipe (Aristolochia macrophylla) is a gamble in hardiness, but give it a try. It’s rambunctious and casts a deep shade with its large, tropical-looking leaves. A hardy, fast-growing native whose foliage turns scarlet in the fall is woodbine (Parthenocissus quinquefolia). Silver lace vine (Polygonum aubertii) is another option. It’s vigorous and blooms in foamy cream panicles in late summer and early autumn.