Acer Rubrum

Class

Dicotyledons

Division

Angiospermae

Family

Sapindaceae

Order

Sapindales

Genus

Acer

Species

rubrum

Description

Polyennial deciduous tree with an upright habit and dense rounded or oval crown. The Red Maple is widely appreciated for the elegance of its plant architecture as well as for its green foliage that gradually changes to warm, bright colours in its autumn livery. Suitable, as a single specimen or in groups, for medium to large outdoor spaces such as gardens, parks, squares and large flower beds.

Variety description

Tree of American origin that is becoming increasingly popular due to its aesthetic qualities and adaptability. Medium-sized tree with a compact ovoid regular crown, very tidy and elegant in appearance. It has some growth problems in limey and too dry soils, especially when young. However, it is a rustic and robust tree of wide use. Light green foliage that turns a brilliant deep red colour in autumn, tending to orange for some varieties. Colouration is limited by soil type and drought. Flowering beautiful, simple, but not scenic. The root system is deep in the soil, densely branched and well distributed, with numerous secondary roots requiring loose, fertile soil. Sunny exposure and also tolerates partially shady areas. Tree with numerous interesting varieties in terms of shape, size and colouring. Suitable for scenic and landscaping use in urban green areas, gardens and hanging gardens. Long-lived plant that does not require pruning and is resistant to urban tree diseases.

Curiosities and special features

The generic term Acer derives from acer acris or pointed, referring to the pointed lobes of the leaf blades, while the specific epithet rubrum derives from the reddish hue of the flowers, petioles and leaves in autumn.

Origin and distribution

Native species of north-eastern America, from Quebec to Minnesota, to Florida and East Texas.

Leaf

The leaves have a palmate lamina with 3 or 5 lobes, a pointed apex and serrated margin.

Flowering period

It flowers from early spring to late spring for a duration of 15 to 25 days, preceding the appearance of the leaves.

Leaf colour

Unicoloured, green above and grey-green below, turning to deep red or orange during a scenic autumn foliage process. Colouration is limited by soil type and drought.

Plant height

The height of the plant varies from 4 to 20 m, depending on the growing conditions and the variety; in general, it is a second-sized tree.

Lifespan

Polyennial deciduous plant.

Where to plant

Due to its aesthetic value and adaptability to different soil and climate conditions, it is suitable as a tree for flowerbeds, gardens and parks, rock gardens, large flowerbeds and road roundabouts, large pots, open field

Stem

The stem is woody with cracked bark; the variety has no thorns.

Flower

The flower is pom-pom-shaped, medium-sized, with a pinkish corolla and shaded petals. It flowers from early spring to late spring, with a flowering period of between 15 and 25 days. It is not particularly attractive to pollinating insects.

Growth

Long-lived tree with medium to vigorous growth.

Plant habit

The habitus is erect with compact ovoid regular foliage, very tidy and elegant in appearance.

Branching

The abundant branching of the red maple allows for a dense, thick foliage.

PH

Like many other species belonging to the botanical genus Acer, it requires a soil or substrate pH of between 6.0 and 7.0.

Soil preparation

Before transplanting at the end of autumn, choose the most suitable location in relation to the needs of the plant and use a spade to make the planting hole of a size proportionate to the root ball. Bury sand if the soil is too compact and not draining, also add organic matter and level the soil well.

Sun exposure

Requires exposure to bright shade, full sun.

Ideal climate and temperature

The ideal temperature is between 0.0 and 30 °C.

Use

Appreciated for its bearing and elegant foliage as an arboreal plant in:

Ornamental Outdoor Landscape Design Landscaping

Hardiness

Low to medium hardiness plant.

Soil

It prefers medium, structured, well-draining soil with organic matter. It may show growth problems in calcareous and too dry soils.

Difficulty

Following proper planting at the new site, cultivation of red maple is fairly easy, with a medium level of management effort required.

Growing tips

Some specific tips and cultivation aspects to achieve better vegetative growth of the red maple:

Balanced fertilisation Avoid over-watering Plant which adapts very well to cold winter climates and also thrives in frozen soil conditions. Exposure to direct light Correct pruning

Planting

For transplanting, adopt an average density of 1500 plants/ha, choosing healthy specimens, free from abiotic and biotic stress conditions. Always identify the planting site in advance in relation to the growth conditions required by the species according to the principle of 'the right plant in the right place'. Place the root ball in the previously dug planting hole, keeping it well compacted around the root and keeping the collar of the plant off the soil surface, then water after planting without causing water stagnation. We recommend the use of supports to be tied on with specific clips or elastic bands.

Pruning

The red maple does not require pruning, it is advisable to leave it to develop freely according to the natural architecture of the plant. Remove any damaged branches.

Propagation

Propagation is by layering, cuttings or seed.

Watering

Allow the soil to dry out slightly between one watering and the next, preventing both water stagnation and dryness. Water more frequently in summer if the season is hot or torrid. Observe the turgidity of the leaves to see if the plant needs water; if they are bent down or cracked, it means there is a water shortage.

Fertilising

During soil preparation, carry out a basic fertilisation with slow-release fertiliser specifically for ornamental plants. After proper establishment in the new planting site, intervene during the spring period with constant and balanced fertilisation; at the same time, the soil can be corrected if it is too acid or limey.

Edibility for humans

Non-edible Species.

Tip

Use organic potting soil with sand or expanded clay to promote root drainage. The plant should never be pruned; leave it to develop freely according to nature.