All newly planted Clematis benefit from hard pruning, no matter how old they are. Your plant will catch up that 2 years worth of growth in no time after it is established :)

Thanks! I will go ahead and cut it back - how far down do you think?

I would do it to six inches but many are not so bold. Up to you.

Did you bury the crown 3-4 inches deeper than the nursery pot when you planted?

What you want is to force new vines up from the crown and for the cut ones to sprout two or more where they were cut. The lower you cut, the more bushy the vine and more flowers.

I buried it a couple inches deep.. I was bold and cut it back!! Thanks

Toss some alfalfa meal or pellets or tea on it. Seems to encourage more vines.

Dr. Ruppel is magnificent. I did as suggested above when I planted 3+ years ago -- deeply planted, actually on a slant, with a great, enriched hole, then pruned it back. It is an amazon clematis, I think because it was given a good start. Figure that it will take several years for it to show itself and will love you for taking care in preparing its bed.