I believe any garden, no matter how small, should have a tree. And acers, or Japanese maples, are the perfect choice for any garden style and size.
They have lovely character and texture that make them the perfect focal point. They will brighten up a dark corner and make a striking feature tree. They also look elegant draping over a path or overhanging a pool or water feature.
Acers are commonly called Japanese maples, not surprisingly because they mostly originate in Eastern Asia, including Japan, China and Korea. Acers fit perfectly with oriental garden designs, but the range of colours and leaf shapes means there is something for every garden.
Many acers have broad, palm-shaped leaves, but others have foliage that is divided and dissected into intricate shapes. Some leaves are so delicate they have a lacy appearance.
Japanese maples come in a wide range of colours, from deep greens to yellow, gold, purple and variegated leaves. The foliage turns incredible rich tones in autumn, going through shades of fiery reds, oranges and gold.
The best acer varieties
Most acers belong to three groups, Acer japonicum, Acer palmatum and Acer shirasawanum. The popular Acer palmatum ‘Bloodgood’ is a striking purple-leaved variety.
Acer japonicum ‘Aconitifolium’ and Acer palmatum ‘Osakazuki’ have rich red leaves. And look for Acer shirasawanum ‘Aureum’, which has golden pointy leaves with red-tinged edges (above).
Where to grow acers
Acers are usually slow-growing trees, with some very slow varieties available. This makes them perfect for small gardens as they remain a manageable size. They seldom need pruning and don’t cast too much shade. They can even grow in containers.
Some varieties of Japanese maple can cope with full sun, especially those with green and purple leaves. Red-leaved trees need some sunlight to develop a rich colour. But hot, strong sunlight can scorch the delicate foliage of golden, variegated and dissected varieties.
Plant acers in a sheltered spot where the foliage is protected from the strongest midday sun and cold or drying winds that may damage the leaves. Young foliage can be susceptible to late frosts.
How to grow acers
Plant acers in well-drained soil that is moist and rich. Add plenty of compost to lock in moisture and make sure the ground doesn’t dry out. Get a three-step guide to planting trees here.
Cover the ground with a deep mulch of compost or leaf mould. This holds in water and prevents weeds from growing. Make sure the mulch doesn’t touch the tree’s stem or it may cause it to rot.
Acer trees can suffer from drying out because they have shallow root systems. This also means you should not plant too much else immediately around the trunk.
Most Japanese maples should not need pruning at all. They develop into a balanced shape on their own. However, you can take out crossed branches that spoil the shape.
Acer palmatum should be pruned when fully dormant (November to March). This is because the trees can bleed sap when cut, which weakens them.
How to grow acers in containers
Japanese maples will also thrive in pots. Choose a large, stable container with plenty of drainage holes. Terracotta pots should be lined with plastic to reduce water loss through the sides, but remember to put drainage holes in the bottom.
The tree will only need repotting every few years, so plant in a loamy soil-based compost like John Innes No.2 or No.3. Its high nutrient content ensures there will be plenty of food for the acer. You should also add liquid feed or general purpose fertiliser in spring and autumn.
Add a layer of pebbles or gravel over the top of the soil to lock in moisture. Water with collected rainwater where possible. You can also stand the pot in a tray and fill with water to create a reservoir during dry periods.
Container-grown acer tree roots can be susceptible to frost during harsh winters. Move pots into a more sheltered spot or wrap the pot with bubble wrap and tie with twine.
Repot the tree into a slightly larger container every few years. April or September are the best times to repot acers.
Planting companions for acers
Acers are often planted alongside other Oriental foliage plants such as bamboo, ferns, hostas, Japanese ilex and laurel.
They also shine alongside other trees like holly, pine and yew, as well as decorative trees like magnolias and flowering cherry and plum trees. And flowering plants like camellia, azalea, wisteria, hydrangea and rhododendrons are all perfect partners for Japanese maples.