Red maple (bot. Acer rubrum), also known as red maple, red maple or swamp maple, is a fast-growing ornamental tree. In spring it is an eye-catcher with its abundant flowering and in autumn the wood with its attractive red colored foliage provides a splendid color in the garden. The tree is not only a real eye-catcher, but also a practical design element in the outdoor area. Its round treetop throws cooling shade in summer and provides privacy for the house and the outside area.
Easy to care for and undemanding: the red maple is not only very popular in its home country, the USA. In Germany, too, it is one of the most popular ornamental trees. And if you don’t have enough space in the garden for the tree, you can add a splash of color on the terrace with a bonsai tree. We explain to you what to look out for when choosing the location, how you can promote growth with the right care and how you can identify and combat any diseases in good time.
Red maple: origin and varieties
The red maple belongs to the soap tree family and is native to North America. Nowadays it is common in eastern Canadian and American forests, where it grows at an altitude of 400 to 1,600 meters. Especially during the “Indian Summer”, a dry and warm weather period from September to October, the wood inspires with its red foliage. Although it is not indigenous but has been brought to Europe, the tree has become an important part of the ecosystem and, as a “bee tree”, it contributes to bee protection.
Since the wild species can reach a height of up to 30 meters, several lower varieties for garden bred. The hobby gardener can find the following ornamental trees in stores:
1. The “October Glory” variety is an ornamental tree that can reach a height of up to 12 meters. Its dark red branches, gray-blue trunk and beautiful autumn colors make it an eye-catcher. The tree retains its red colored foliage until December. Suitable as: a solitary tree in the front garden, which offers privacy and sun protection for the terrace. Sensitive to frost and therefore only widespread in southern Germany.
2. “Northwood” is a very hardy plant that can easily withstand snow, frost and strong winds. Loses its leaves sooner than the “October Glory” variety. It grows up to 12 meters high and is mainly used as a solitary tree in medium-sized gardens.
3. “Snow fire” is a fast-growing variety with brightly colored red-orange-yellow-green leaves. In autumn its green leaves turn yellow to intense fiery red. The crown is broadly pyramidal, the ornamental tree reaches a growth width of up to 10 meters and a maximum height of 15 meters.
4. The crown of “Red sunset” is also pyramidal and broad. This variety sheds its foliage at the end of autumn and is popular for its beautiful red foliage. The ornamental tree is very frost-hardy, even in sub-zero temperatures it can thrive without any problems.
Red maple: appearance
The red maple is a medium-tall tree. The cultivated varieties reach a maximum height of 12-14 meters and are usually around 8 meters wide. With an average increase of 50 cm per year, the wood belongs to the fast-growing trees. It is a heart root, which means that its roots first develop downwards and only then does another system form under the earth’s surface. Heart roots are considered to be very undemanding and can adapt to the terrain. The fast-growing roots can lift terrace coverings and garden paths.
Growth habit and crown
Depending on the variety, the red maple can grow either as a standard tree or as a multi-stemmed shrub. Only a few varieties have a compact, upright habit. Most of them have a broad crown, varying from conical to rounded. The branches are dark red to red-brown and the tree trunk is gray-blue in color. After just four years, the tree can provide shade and begins to lure bees and butterflies into the garden. In summer it is often used as a nesting place.
Red maple: leaves
The tree leaves are shiny, three- to five-lobed and arranged opposite one another. The tree turns green in spring and retains its green foliage in summer. Only at the beginning of autumn, i.e. in September, do the leaves first turn gold, then orange and then turn deep red. It is precisely for this saturated red nuance that the red maple is so popular. It brings variety to an otherwise boring autumn garden and gives the front garden an additional splash of color. If the winter is mild, the new budding can start as early as January. The leaves are only very poisonous to horses.
Flowers and fruits
Red maple has a short flowering time of just two months. The umbel-shaped flowers, like the new shoots, are colored golden brown. A month later, the tree produces fruits that fall off in early summer. It is precisely this early flowering period and fruit formation that are of great importance for the wild bees. Because with a good to very good nectar and pollen value, the red maple proves to be an important food source for the development of several wild bee colonies.
Red maple: demands on location and soil
Red maple is an undemanding tree that feels good in partial shade as well as in sunny locations. The tree cannot take heat, which is why the south garden is not ideal for it. The warm, west-facing garden or a plot of land facing east or north are more suitable. Otherwise, the wood does not have any special demands on the location and can thrive without any problems in frost, snow, rain and wind.
When choosing the location, you should also expect a rapid increase in height and width. The red maple cuts a particularly good figure as a solitary tree in the middle of the lawn. So he has enough space to develop his root system. Its crown will also grow in the years to come, so you should leave at least 10 meters free around the tree or plant it with ground cover and low flowers.
As for the soil, red maple is also undemanding. A loose, nutrient-rich, moist and slightly acidic soil proves to be optimal. Long dry periods in summer do not bother him. It can grow quickly in sandy soil as well as tolerate short-term flooding. The only problem is calcareous, compacted soil in which waterlogging can form. The ornamental tree is moderately salt tolerant.
Planting and transplanting
Spring is the right time to plant a red maple tree. After you have chosen the location, you need to dig a hole that is at least two, and ideally three times as wide. Loosen the soil and improve the soil with quartz sand if necessary. With compost you can increase the humus content of the earth.
We do not recommend transplanting the red maple. He really can’t take it well and there is a chance the tree will die. If there is no other option, then you should dig a hole 1 meter wide and at least 80 cm deep around the tree and only then try to remove the tree.
Red maple: care, pruning and propagation
Red maple can do well with minimal maintenance. He only needs water if there is a longer dry period in summer. As a rule, you do not have to add fertilizer either. You can only fertilize young trees once in spring. However, as long as the soil meets all requirements, you no longer need to provide the ornamental tree with fertilizer after the first year. You do not have to cut a red maple either, as the tree does not need it on the one hand and does not tolerate a cut very well on the other. If its crown is too dense and frizzy, you can cut off individual branches at the end of summer.
As far as propagation is concerned, it is basically possible to propagate the red maple by sowing. In most tree nurseries, however, the trees are propagated by cuttings. For this purpose, shoots 15-20 cm long without flowers are cut off at the end of spring or the beginning of summer. If you want to try this method, fill a flower pot with potting soil and insert the shoots halfway into the soil. Place the bucket in a shady to partially shaded location and cover the pot with transparent film. Ventilate the plant daily by removing the foil for half an hour. After a year, the young tree is basically ready to be planted in the garden.
Red maple: use as privacy and sun protection
Red maple feels right at home in a medium-sized to large garden. It can provide cooling shade over cozy seating areas in the garden. The tree also cuts a fine figure at the edge of the garden and automatically attracts the attention of passers-by. Since the tree grows quickly and gets quite tall, you will need to allow a marginal distance from your neighbors and your house when planting. When planning, also consider the regulations of the local authorities regarding trees. Basically, you should follow the following rules:
- Always plan a limit distance of at least three meters to the neighbors.
- Leave a minimum of two meters between the tree and the terrace. In this way, damage to the terrace surface caused by the roots can be avoided.
- A distance of 5 meters from your house guarantees that sufficient sunlight will enter the house even after 5 or 10 years.
Red maple: diseases and pests
Red maple is not susceptible to most pests. However, if the soil remains dry for a long time, dark spots can form on its leaves. Conversely – if it has to endure waterlogging for a long time, then it can be attacked by various fungal diseases. If it is waterlogged, it is also endangered by aphid infestation.
Bonsai red maple
If you are looking for an easy to care for and extremely robust houseplant, then this plant is for you. Bonsai maples have few requirements in terms of location and soil and fascinate with their beautiful foliage, which turns green in summer and red-brown in autumn. The trees in small format are up to 40 cm high and 20 cm wide, so they are super compact. You can display them on a dresser or side table, or arrange them with other plants as you wish. However, the Americans cut a fine figure as soloists. And when it comes to beautiful leaves and treetops, they are in no way inferior to their big relatives.
The houseplants are ideal for beginners because they can thrive in a warm room. However, it is not the sunny location that proves to be optimal, but a location in partial shade. A substrate for bonsai trees with a proportion of sand offers the best conditions for their rapid growth. As far as the addition of water is concerned, you have to make sure that the soil neither dries out completely nor becomes too damp. The plants are very sensitive to waterlogging and can hardly tolerate them.
The bonsai maple can spend the winter at home, in the summer you can display it on the terrace or balcony. The tree can stay there until late autumn. If the temperatures drop below 0 degrees, then you have to bring the bonsai tree back into the house. First, place the plant in a cool, dry room until it gets used to the temperature change. Only then can you put them in the limelight in your room.
Bonsai maples usually cost less than other bonsai trees, but they look just as beautiful. They are also suitable as gifts on special occasions.
Red maple is a long-lived tree that can live between 70 and 130 years in the garden. Undemanding and fast-growing, the ornamental tree is the perfect addition to the large garden. It can be staged particularly effectively as a soloist and cuts a fine figure in the front yard.