I am about to be tented and need to protect my landscape
I have an ancient and large wisteria against my house. It is totally dormant right now. If they cannot get the tent behind it - will it die? Thanks, Linda
Certified GKH Gardening Expert
There is a high probability that the fumigation chemicals will harm the plant and cause die-back and possible mortality, depending on what chemistry they are using. Ask the pest control company to advise you on this, they should be knowledgeable and experienced with an issue like this. And ask them to provide you with a product label for the material they are using. The product label is not just a sticker, it's a thorough disclosure of all aspects for safe and effective use, including environmental precautions, including possible "phyto-toxicity" issues.
With the plant in full dormancy the potential for absorbtion won't be a much as if it were in leaf. Even if the plant survives the flower buds that are present may be lost, and the flowering missed this year.
This may not be practical with a mature wisteria as you describe, but one option is cutting back the plant as much as is needed to get the tent behind it, even if you have to cut back to near the ground level in order to save the root system. If that is not possible, then water the root zone, even though the plant is dormant, and take your chances. Water again when the tent is removed and wash off the stems with a jet of water as much as possible to limit continuing absorption. Fertilize as soon as new growth occurs in early spring.