This Acer was pruned back in November and has looked amazing ever since. It's now had such a growth spurt it has taken over part of the garden - what can you do?
The issue is the root structure below the soil wants to produce a large tree and this is what the new growth is doing.
The best time to prune this beautiful plant is over winter and early spring. If you prune it now (June/July) you run the risk of losing it as the sap is still rising, and the plant could go into shock. It needs to be left until the colder months.
While the tree is in leaf work out what needs removing - look at raising the canopy level through pruning underneath.
It's really important to fight the urge to prune in the summer - you'll only regret it. Only prune when the tree is dormant.