If you plant Passiflora vines, which is food for butterfly caterpillars, they WILL eat all the leaves. The vines will leaf out again. They won't eat the stems - just the leaves.

I wouldn't do anything to prevent this - that's why I grow them.

The pesticide won't affect the plant's ability to grow back, but one shouldn't use pesticides unless there is no other choice.

I would leave the vines on the trellis and they will grow new leaves.

In your zone, it will leaf out again this year.

He is correct, why worry when for every leaf eaten ten more sprout out. Passiflora is real tough, let the butterfly larva have a feast. As it is winter is near and bye bye all leaves.

soapy water spray could help.
i would use good natural soap, but some people will use any. and dilute it with lots of water.

this works on other kinds of bugs as well.

Unfortunately, they will and do kill the varieties that they really like. They will kill Constance Elliott at my house. They'll eat all the leaves, all the small stems and all the green off the larger stems. Nearby, is a full, leafy, purple passionflower. You can spray if you want to. You can identify your pest. Go to your local independent nursery and tell them you have butterfly caterpillars. They'll tell you what and how to spray it. BT is considered an organic spray, but I don't think it works very well. Picking them off works pretty well.

If you watch for them and pick off the early ones, you won't have as much trouble. If you let a generation of butterflies grow, they'll come right back to your passionflower to lay their eggs. So, just as your passionflower is making a recovery and leafing out again, they'll be back to strip it again.

My other passionflower doesn't attract enough butterflies to matter (some kind of maypop hybrid - lost the tag).

Strange.....

bk