Too much water? That will cause leaf drop. Between your drippers and the wet, cold weather, perhaps they are getting too much moisture--especially if the drainage is not as good as it could be.

Just a thought.

Kate

What exactly do the leaves look like before they drop?

And what do the canes look like, where the leaves dropped?
Are any of them, if you look VERY closely, slightly withered?

Jeri

If you shake the plants, are they securely in the ground?

The leaves and canes looked fine and what remains still does except for a little black spot from the rain.

I think they weren't getting enough water, because the dripper valve is leaking so I don't think the drippers were working as well as they should have. I gave them a good soak with a hose and soaker so I will see if that helps. I have to replace the valve and keep checking to see if the drippers are working. I have had guests for the last 3 weeks and way behind on my maintenance.

Thanks everyone for the replies.
Clare