United States 
Hello I'm in zone 4 USA and purchased a Clematis Duchess of Edinburgh late last summer. Over winter I mulched it 6" high around crown and inside an inverted pot to cover stems. We've had a ridiculous amount of rain and cool temperatures the entire month of May. It's now early June 2017 and no signs of new growth or growth on old wood. I trimmed woody vines (2) to about 12". The roots are very healthy and plump as I dug way down to have a look. There's a Clematis Nelly Moser a reasonable distance from it and it's thriving. I have a year guarantee on this perennial and I'm wondering how long should I wait to see new growth before digging it up to take back. Later in the week and the following week the weather is supposed to improve well into the 80's and even 90. Any guidance is greatly appreciated.
7 Jun, 2017
Answers
welcome to GoY. try scarping a little of the bark back on the remaining stems with your thumb nail. if it is green then it is still alive, if brown that section is dead. if you don't mind leaving it there then give it another 3 months, then if no sign of growth dig it up and take it back.
7 Jun, 2017
I am in zone six having relatively cool weather with rain every few days and now my garden has turned on the afterburners and is zooming up. I have Monarda reaching six feet in height and they still have yet to flower! I would be patient. Many times I have given up on a plant with it giving me a minor performance one year to turn absolutely brilliant the next. Talking about being brilliant, thank you for joining GOY! Best Regards.
7 Jun, 2017