What is happening to my Clematis ‘Avalanche’?

I have three of these evergreen Clematis ‘Avalanche’ growing up trellises and onto an arbor around the garage doors. This is their third summer there and they have been growing and blooming very well. I even have a dark-eyed Junco pair with their second nest of the season in the clematis up on the arbor. I have been fertilizing it once a month with Rose fertilizer (as I’ve seen you recommend, while not in bloom) in the growing season. They are planted about a foot away from the cement garage pad, about half way out from under the eave so they get rain and there is a 6” layer of fine to medium bark over and around the root zone to keep the roots cool. About three weeks ago, leaves started turning yellow and died leaving the vine with only a little bit of the newest growth but these, too, are flagging. And now, it appears as though another one is starting to die. Help! What is going on and what do I need to do? I love the evergreen foliage framing the garage doors and I don’t want to lose them. If it cannot be saved, what can I use instead? I live in a Zone 8a area but I like to use Zone 7 plants as much as possible to be safe. Thanks in advance for your help.

Posted by Debbie Nighswonger on June 22, 2020