Japanese maple is known for its colorful foliage in varying shades of red and delicate leaf shapes. These pretty shrubs or small trees are real gems. But why do the red leaves on the maple sometimes turn green?

In a nutshell

  • not all species have permanently red leaves
  • some only red when sprouting or in autumn
  • Leaves green the rest of the year
  • Green coloring normal for many varieties
  • look for other causes of greening in the location, soil or fertilization

Green leaves not uncommon

Not every red Japanese maple shines in a beautiful red during the entire growth phase. There are species that only have a reddish coloration when they sprout in spring and/or autumn and are green for the rest of the year. In most cases, this is a completely natural process. The red coloring protects the leaves from intense sunlight.

For this reason, they increasingly form this red pigment at the beginning of budding. If the leaves are larger, they usually no longer need protection and turn green. In contrast, Acer palmatum 'Atropurpureum' shows its magnificent red coloring from spring to autumn. Despite everything, there are red Japanese maples that turn green for other reasons.

Green foliage on the Japanese maple is not always a cause for concern.

Notice: The term Japanese maple often includes the actual Japanese maple (Acer japonicum) and the Japanese maple (Acer palmatum) with all their varieties.

causes and remedy

If the leaves of the red Japanese maple turn green, this can also have other reasons that can be attributed to mistakes or problems in care. Here we list the most common causes of "abnormal" greening and what you can do about it.

Unfavorable site conditions

Green Japanese maple can be caused by an unfavorable location. A lack of or too little sunlight, as well as too much or too intense sun, can lead to the red coloration being only weakly pronounced or not appearing at all and the leaves turning green. A change of location promises help.

  • Red color depends on variety and location
  • most intensively at the optimum location
  • already consider the requirements of the individual species when purchasing
  • bright and semi-shady location almost always right
  • in spring and autumn locations in full sun are unproblematic
  • Protect leaves from intense sunlight in summer
  • otherwise, burns may occur
  • Locations near a body of water are ideal

Tip: Japanese maple has very special light requirements, which is why it can sometimes be advisable to cultivate it in a bucket. In this way, it is always possible to put them in the right light and avoid damage caused by the sun.

Too high pH

If Japanese maple is in a soil with a high pH value, this can also be the cause of the leaves turning green. A pH value that is too high, i.e. in the basic range, can hinder the absorption of nutrients, even if they are present in sufficient quantities in the soil. The result: the red maple turns green.

  • Slightly acidic to neutral pH between 4.5 and 7 is optimal
  • alkaline soil produces green leaves
  • calcareous substrates unsuitable
  • Soil should be gritty-loamy or sandy-loamy
  • also lime-free, permeable and well drained

Correct pH: help

  • for basic substrates: acidic rhododendron earth
  • Mix soil that is too heavy with sand and coconut humus
  • make wet soils more permeable with 30-50 percent sand or gravel
  • additional 10 cm thick drainage layer on the bottom of the planting pit
  • only water with rainwater if possible
walnut leaves

Tip: If necessary, the pH value of the soil can also be lowered with the composted leaves of conifers, walnut trees or oaks. The current pH value of the soil can be easily tested using a corresponding test from the hardware store or garden center.

Too nitrogenous fertilization

The foliage color of Japanese maples is significantly influenced by fertilization. If Japanese maple is fertilized with too much nitrogen, the leaves, especially red species, will fade and turn green. In addition, fertilizers that are too nitrogenous make the plants more unstable and more susceptible to cold. When fertilizing these plants - with the exception of potted plants - less is definitely more, otherwise there is a risk of greening.

  • moderate to low fertilization recommended
  • a dose of compost in the spring is often sufficient
  • Fertilize potted plants every three to four weeks
  • with high-quality complete fertilizer or special maple fertilizer
  • Here, too, it is essential to pay attention to the dosage
  • do not fertilize at all after July
  • Maturation of this year's shoots could affect fall colour

Tip: The red is usually the most beautiful and intense in the plants that are fertilized the least, even if they are actually heavy consumers.

frequently asked Questions

Which Japanese maple leaves are red throughout the summer?

The Japanese maples, which shine in different shades of red from spring to autumn, include Japanese maples (Acer palmatum), for example the varieties 'Shojo', 'Yugare', 'Beni' and 'Burgundy'. Also worth mentioning is the Japanese fire maple (Acer japonicum) 'Atropurpureum'.

Are there red Japanese maples that are particularly suitable for planting in containers?

In principle, almost all varieties of Acer palmatum can also be kept in tubs. However, dwarf varieties such as 'Shaina' with deep red foliage all year round, 'Skeeter's Broom' with red foliage in spring and autumn or the 'Red Pygmy' variety with dark red foliage that turns green in summer are particularly suitable.

What do you have to pay particular attention to with specimens in the bucket?

The most important thing is good drainage and a sufficiently large bucket. The larger it is, the fewer problems there will be with care and wintering. If possible, it should be made of clay or terracotta. These materials release excess moisture to the outside, so that the substrate is better aerated. Since these plants are often in the same tub for several years, it is important to ensure that they are supplied with water and nutrients regularly.

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Garden plants