I have two vines, a Blue Moon Wisteria and a clematis Jackmanii, growing on a wooden fence (they have been there for 12 and 14 years respectively). I’ve been advised that the wood is deteriorating and that I should get the fence rebuilt. When would be the best time in the year to do this, and how can I best save the vines so that they can re-establish themselves on the new fence, if that’s possible? The wisteria in particular has interwoven itself into the lattice at the top of the fence. I would appreciate any advice!
Thank you for contacting the Toronto Master Gardeners.
What a wonderful display your vines must provide with their different bloom times. The challenge will be not only to protect the vines during the time the fence is being rebuilt but also not foregoing any blossoms.
Time the replacement work for early September. Just before the contractors are due to begin, cut the clematis down to 24”, dig out the largest possible root ball, place it on a tarp or into a pot and move it into the shade. Ensure it is kept damp but not soggy. Cut back the wisteria to about 36” and place boards over the area where the roots are growing so the contractors will not compact the soil. Assuming the work will take about 2 weeks, this timing will allow the clematis to be re-established before the ground freezes. Water both vines well when the work is completed.
Tips for replanting the clematis.
- Prune out some of the oldest, thickest stems to encourage new stem growth.
- Take this opportunity to divide the plant if necessary. Dividing will renew vigor and promote flowering.
- Make sure to dig a hole at least twice as wide as root ball (because soil will have gotten very compacted by work).
- Water the hole deeply and allow water to drain.
- Plant deeply (this promotes its survival if above ground growth gets killed by wilt or anything else). The top of the root ball should be about 4 inches below soil surface.
- Plant on an angle so the stems are tilted towards support/trellis. This will help with attaching stems to trellis as the plant grows.
- Top dress with an inch of compost (don’t add compost or other fertilizer to the hole), and then a layer of mulch. Keep both away from the stems.
- Water well and keep watering well every few days until freeze-up, but test first that the soil is dry 2 inches below the surface before watering.
Here is some further reading from our library on pruning of Wisteria and Clematis.
https://www.torontomastergardeners.ca/askagardener/can-i-prune-my-wisteria-now/
https://www.torontomastergardeners.ca/askagardener/pruning-clematis-and-grape-vine/