Last year, I suggested to a client that we plant a wisteria “tree” in one of her pots. I had “made” wisteria trees in the past by using a new plant that started to branch from a single upright at about 24 inches. I planted them in pots and began forming the “canopy” by tying selected vining pieces to bamboo poles to form the shape. This involved continual and careful pruning and regular reshaping. In two years, I had baby wisteria trees that became spectacular.
But this spring I found no vines that would work. They were already too tall. As I peruse the garden centers and nurseries this year, I will continue to look for some I can train. The results are so fantastic and the challenge is similar to taming a wild beast!
I still remember, years ago, seeing a wisteria in full bloom as tall as a pine. Wow, I thought, a wisteria tree! It was breath-taking, dripping with lavender flowers. I inspected to find that the wisteria had used the tree as a structure and the tree was almost dead, having been strangled by the vine. Soon after, the tree and wisteria had been removed, probably with the same large machine that removed all of the other plant material in preparation for a new house. This might be the best way to remove wisteria!
The garden centers and nurseries have Asian and American wisteria at this time, and remembering those exquisite and fragrant flowers, it is tempting to plant one. But wisteria is similar to bamboo, beautiful and exotic but needs specific planting situations and attention forever or it will become dangerously invasive. Because of the way it grows, if left unattended it can eat your house and then move on to eat the neighbor’s or infest the trees in a very large area.
Wisteria wants to twist around something to climb and can climb up to 65 feet. As it twists around its host, it strangles the host. In fact, if wisteria twists around itself, one piece will strangle all others. As it climbs, it sends out side tendrils and tendrils from the trunk to find new hosts and they send out new tendrils.
The bottom of the plant can grow to 15 inches or more and new tendrils grow from the base, at ground level and travel enormous distances. I have a client that has a small vine attached to his house. The base is under the steps so I cannot get to it to trim the tendrils at the trunk. He lives in the woods, and I have scoured the area removing tendrils as far away as 80 inches. If a piece of tendril is left in the ground, it will sprout and continue to grow. Every time I go to this house, I go into the woods to look for telltale wisteria leaves. This plant does not bloom! Young ones, 6–7 years old, usually do not.
Here’s the good part. If trained and maintained, the wisteria can be exquisite. It needs a location where it can show off and something to climb on after the trunk becomes large enough. If the top is clinging to something, it can stand alone. A pergola is a good location, as the flowers will hang underneath and over whelm the viewer with its beauty and fragrance. The pergola should be substantial to carry the weight of a mature vine. It must be constantly inspected and pruned. Growth from the base must be removed and new tendrils must be cut. This also encourages new flowers. It must be pruned to keep it from pulling the pergola apart. If you plant it next to a building, it must be kept off of the building so it will not lift the roof or peal off the shingles.
American wisteria is more well behaved, grows shorter tendrils, is not as vigorous, and blooms on and off through the summer. I would still plant it with the above in mind. Actually, I would only plant wisteria in a pot and then watch the hole in the bottom for escaping tendrils!
Jeanelle Myers is a professional gardener, landscaper and consultant. For gardening discussion you can call her at 631-434-5067.