The Japanese maple (Acer palmatum) is a deciduous tree from Asia with beautifully colored foliage. In spring and summer, leaves can be yellow, green or bright pink, while autumn brings spectacular shades of bright gold, crimson, orange and reddish-purple. Acers, as they're also called, come in many varieties. There are multi-trunk and single-trunk trees, for example, and a weeping variety that's wider than it is tall, with dramatically sculpted limbs. Overall, the trees range in size from dwarf maples that can be grown in containers on up to 25-foot (7.5-meter) giants. And they sport a variety of different leaf shapes and silhouettes, too.
While Japanese maples are slow-growing trees, one of the reasons they're popular is that they're easy to grow and don't require a great deal of care. Planting is best done any time from October through March in a partially shaded area protected from the wind. Acers do best in well-drained, loamy earth, since they have a shallow root system. Ideally, the soil should have a pH between 5.5 and 6.5.
Once established, Japanese maples need little in the way of watering, pruning and fertilizing. And they're not prone to insect infestations or disease, either. Perhaps the only downside to this tree is that it's pricier than many others.
Here's how to care for your Japanese maple by season.
Japanese maples are most vulnerable in the spring, as they leaf out at the first hint of warmth. This means late-spring frosts are a danger. If low overnight temps are predicted, cover your tree.
Acers prefer moist soil — not too wet, but not too dry. To help stave off summer's heat, mulch with 2.5 to 3 inches (6 to 8 centimeters) of shredded hardwood bark to keep evaporation at bay. Then water deeply twice a week, and more often if the tree is young or in a container.
While Japanese maples don't attract many insects, you may find aphids invading now, which will mottle their leaves. If you don't want to spray against the pests, you can try companion planting: petunias or nasturtiums tend to keep the aphids away. At season's end, lighten up on the watering. This will enhance the colors in the tree's fall foliage display, which is just around the corner.
Some experts advise pruning your tree in early fall, while others recommend waiting until the tree is fully dormant (generally November through January) because fall pruning causes the tree to bleed sap. Whenever you decide to prune, keep the cutting to a minimum, trimming mainly dead branches, twigs growing vertically and any branches that are crossing or rubbing against each other.
After pruning, mulch to protect from winter's freeze. Since the roots of your container-grown maple are susceptible to the cold, cover the pot in bubble wrap and place it on a brick or other protective object. Finally, pluck off any dead leaves remaining.
As we said earlier, fall is the best time to plant a Japanese maple.
There's not much maintenance required for Japanese maples during the winter, with one exception. Make sure to check your tree after a heavy snowfall, as deep snow can snap branches. After such a storm, gently brush the snow off the branches, taking care not to break them yourself. If the branches are coated with ice, leave them alone.
Follow these easy measures, and you'll enjoy a beautiful, colorful tree for many years to come.
Originally Published: May 20, 2011