|This wisteria has a base of about 3" and is out of control. It's wrecking the porch by sending shoots into the structure. What can I do to control it?|
|Boy, once they get established, wisteria are definitely vigorous growers. The best way to get a handle on the growth is to train it while it's young by rubbing out buds as they form along the trunk, and selectively pruning to keep the basic structureunder control. If yours is out of bounds, don't be too afraid to cut it way back.
The general rule of thumb is not to remove more than one-third of the plant material in any one year. So, if you've got a really rangy wisteria, plan to spend about three years re-training it. Right now go ahead and remove the long shoots that are threatening the porch. Identify the worst ones, follow them back to the trunk, and prune them off there. Then step back and look at what remains, and remove the next-worst offenders. In the spring when buds form for new shoots, rub them out if they are too numerous, or if they appear to want to grow in the wrong places. Patience and perseverence will pay off eventually.