Mountain Ash Bonsai Care Guide

Sorbus aucuparia

Mountain Ash Bonsai

Sorbus aucuparia flowers beautifully during the growing season with crisp green leaves complimented by creamy white flowers in the spring. In the autumn, this slender deciduous flourish with orange and gold tints to its foliage. This arresting display is finessed with vivid red berries.

Mountain Ash Bonsai Care Tips

Full sun or only partial shade. This is a robustly hardy species and frost protection is only required for temperatures below -10 degrees C. 

Be sure to not allow the soil to dry out. Throughout the growing season Mountain Ash can be watered daily. During winter they can be watered moderately, judged by soil dryness. 

For trees in training every two weeks is the advised feeding routine. In order to reduce leaf and left size, feed monthly. During the growing season feeding should take place every two weeks. 

Continually trim new shoots to one or two leaves to maintain shape. Late winter is when to prune branches back hard. To encourage branching prune hard in the middle of summer. 

Mountain Ash can be style in all forms excluding broom and formal upright. We recommend using wires with a thickness that matches the thickness of the branch: if the wire you choose is too thick you will damage the bark. If it is too thin, it won’t be effective.

Repotting your tree is an important way to provide a fresh and suitable soil mix and ensure appropriate root health. Repotting your Mountain Ash bonsai should be done every other year once the buds begin to extend in Spring.

Trees that are ready for repotting will require root pruning, a suitable new pot and appropriate soil mix.

When repotting, do not cut back the root mass by a large amount, and choose a well-draining soil mix that has a neutral or slightly higher PH value of 5-6 but not over 7. We tend to use a mixture of different speciality bonsai soils on our trees. Every species is different so please contact us for free soil-mix advice or to take advantage of our repotting service.

Bonsai trees aren’t only magnificent additions to an indoor oasis, they are more than capable of standing out in any garden. Many Bonsai species are incredibly hardy and withstand nature’s colder and damper turns with aplomb making them worthwhile outdoor plants. We have an extensive library of care guides for outdoor bonsai trees. It’s not about selecting the perfect bonsai, it’s about selecting the perfect bonsai for you. 

Mountain Ash Bonsai - Typical Queries

Mountain Ash bonsai can be propagated with cuttings and seeds. Seeds should be sown outside in Autumn. Greenwood cuttings are best to strike in the Summer.

Mountain Ash bonsai can fall to root rot if overwatered. In terms of pests, be watchful for red spider mites, scale and aphids. A reliable pesticide can take care of intruders. Mountain Ash can suffer from fireblight disease. Fireblight is a contagious bacterial disease for plants for which there is no cure. Prune and remove branches to stem the tide. 

As a deciduous tree native to temperate regions, it’s not advisable to keep a Mountain Ash bonsai indoors.