Q.How Do I Prune A Four Foot Single Stem Of A New ( From A Cutting) Bougainvillea?
Last November (2020) a friend gave me a cutting from her bougainvillea. I had it in a sunny window and it grew to about 4 feet in height. I repotted it once. I have had it outside in the warmer weather. I would like to prune to be bushier and to keep it at maybe two feet in height. It is presently blooming on the top 12 “or so. I live in Montreal (zone 5a) so it definitely has to come in for the winter. How and when should I prune it? How should I prune it to have multiple branches? Thanks very much.

Certified GKH Gardening Expert
Your cutting did well! You can lightly prune it after the blooms fade. Cut back a couple of inches on the tip. Any severe pruning should be done when it is dormant at end of winter.
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/pruning-bougainvilleas.htm
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-pruning.htm