Vine maples’ long, multi-stemmed structure requires pruning to maintain an attractive shape. You should plan on annual maintenance pruning to promote new growth while preventing overgrowth in areas where old branch growth is thick. The best time to prune a vine maple is during the winter dormant months or in early spring before the new growth appears to promote a flush of growth. You should avoid pruning from late summer to early winter as it may induce a flush of new growth that may be damaged when the temperatures cool in winter and reduce new growth in the spring.
Make sure to inspect your vine maple throughout the growing season and remove all dead or damaged branches, cutting them off with a clean, sharp pruning clipper at the joint closest to the damage. Remove dead and damaged wood to promote new growth in the areas the branches were removed.
To shape your vine maple, you’ll want to cut off all the superfluous branches, starting from the base and working upward. If you want a single trunk, choose one main shoot and cut away all others at the base. Always remove the major branches or shoots first, and work upward to the smaller ones.
You’ll want to thin out the smallest branches if you want to force growth upward and outward. Maples have leaf and branch buds that are directly opposite each other, so when you cut above a node (the place where the buds sit) the buds on both sides are forced out, giving you two branches for one cut. To keep the tree open and airy, remove one of these buds, directing growth into the other.
You can shorten the longer branches if you want to encourage the tree to be broad and bushy. When you cut back to a node, keep both buds, giving you twice as many branches. Or keep some as double buds and some as single.