Growing Japanese Maples
Position maples in a protected spot, away from strong winds.
In all but the coolest areas they do better in semi-shade.
Morning sun or dappled sunlight are the best options.
They like moisture in their shallow root run, so rich, friable, free-draining soil is best but any that isn’t heavy clay or very alkaline will do.
PLANT by digging a hole four times the width of the rootball and a little deeper.
Mix rich compost into the dug-out soil and fill the base of the hole.
Remove the plant from its pot and gently tease out any circling roots, then position it in the hole and backfill with enriched soil.
MULCH with 70mm of well-rotted organic mulch, keeping it at least 100mm clear of the trunk.
CARE for Japanese maples by watering regularly for the first three years. They don’t need a lot of water but do need it in consistent amounts.
Check that there is sufficient moisture after rain, as shallow falls may evaporate quickly.
PRUNE in winter or summer, removing branches that spoil the shape of the tree and any that are diseased or crossing.
Summer pruning stimulates less plant growth than winter pruning, so you can get away with cutting back a little more and the tree will stay thinned out for longer.
WATCH FOR sucking insects, as scale and mealy bug sometimes feast on young shoots. They can be easily removed with a toothbrush or thumbnail, or sprayed with pest oil.
Aphids can also be a problem, use a soap-based spray or blast with a jet of water from the hose. Caterpillars are a common problem, but just remove, drop and squash them.
Curl grubs are especially dangerous, chewing through the tree’s shallow root system, especially in pots.
Treat them with a spinosad-based insecticide like Yates Success. Fungal problems can be an issue, especially in young plants and bonsai, so don’t overwater, plant too deeply or grow in heavy soil.
Repot a tree with fungal issues into a disinfected pot filled with fresh potting mix. Leaf tips turning brown can be a sign of overwatering or of leaf scorch.
Adjust watering if needed, or consider moving the tree to a more protected part of the garden, or planting screening trees nearby.