The mountain ash can often be found in cities and impresses above all with its decoratively shaped leaves and bright orange fruits. These attract birds magically, which is why the mountain ash can also be an animal-friendly and beautiful eye-catcher in the garden. There are, however, one thing and another to consider when caring for them.
Table of Contents
- Name: Mountain ash, also known as rowan or rowan tree
- Family: rose plants
- Possible age: 80 to 100 years
- Height: 3 to 15 meters
- Flowering period: May to June
- Maintenance effort: low
- Wintereignung: frosthart
- Fruits: berries, slightly toxic to humans and mammals in their raw state
- Propagation: by seeds
- Location: Full sun or partial shade, nutrient-poor, humus-rich substrate
- Special features: sensitive to heat, insusceptible to pests, aggressive roots
- Importance for animals: source of food for birds in winter
This includes the lighting conditions. The mountain ash needs a sunny or partially shaded location. The darker the place chosen, the fewer flowers and berries will develop. A compromise has to be found here, because the mountain ash is also sensitive to heat. Planting close to house walls is therefore not recommended, as these can also store heat and thus damage the deciduous tree.
Due to the light canopy of leaves, the rowanberry donates little shade, which is why it is also ideal for overplanting beds.
The mountain ash or rowan, as the deciduous tree is also known, is often found in urban parks or directly on the street. Because exhaust fumes from cars can hardly harm the wood. If you want to bring the rowan tree into your own garden, you should pay attention to a few factors despite this insensitivity.
The root as a decisive factor
The mountain ash has very aggressive roots that spread quickly in the ground and do not stop at lines and pipes. They should therefore be used away from the sewer system. A root boundary can also help and provide additional protection.
The right time to plant
The mountain ash can be planted from spring to autumn, but planting in spring is ideal. And after the last frost.
Because the mountain ash is hardy, but can be damaged by frost, especially at a young age. In addition, the roots cannot spread or anchor in the frozen ground.
How much space does the mountain ash need?
The mountain ash becomes about two to four meters high and has a diameter of at least two meters. Depending on the age, this can also expand significantly. The network of aggressive roots is correspondingly extensive.
For this reason, a planting distance of around three to four meters must be maintained. However, this does not apply to smaller bushes and plants, but only to other trees.
The mountain ash is undemanding when it comes to substrate. This should only be low in nutrients and humus. Normal garden soil is sufficient. This can be calcareous, acidic or basic. The rowan berries generally don’t care.
However, the soil should not tend to compaction. Sand can be mixed in to loosen it. Clay granules or mulch are also suitable. The latter has another advantage that will be discussed in fertilization.
The maintenance effort of the mountain ash is very low, as are the requirements for the substrate. Occasional watering if necessary, low fertilization and appropriate cutting are sufficient to ensure that the mountain ash thrives.
The mountain ash likes persistent and even moisture. On the other hand, it is sensitive to waterlogging.
The first step is a substrate that stores water but is so permeable that it is not dammed.
When watering, you should also make sure that the top layer of soil has dried off a bit. If it rains regularly, you can completely dispense with an additional water supply. Watering is only necessary at very high temperatures or in dry months.
Also with the type of water one does not have to proceed with special care. Tap water, even if it is quite calcareous, is just as suitable as the softer rainwater.
A watering ditch, i.e. a small indentation around the rowan tree, ensures targeted irrigation of the roots and reduces the amount of water required.
Fertilizing the mountain ash
When fertilizing the mountain ash, mulching the substrate is an advantage. If this was done before planting, additional nutrients are not required. That is true at least for the first few years.
If you did not do this at the beginning or if the tree has been in the same location for several years, fertilization makes perfect sense. A low-nitrogen agent for deciduous trees and decorative woods is ideal. This should be applied around September. After that, it is advisable to water the tree well and abundantly. As a result, the nutrients are distributed optimally in the soil and get to the roots better. On the other hand, the addition of water prevents concentrated nutrients from concentrating on the roots and causing chemical burns.
The trimming is rarely necessary with the mountain ash and is actually only recommended if the tree is to be kept small or if there is an infestation.
Thinning is only rarely required. But if it is necessary, it should be done as soon as possible after the flowering period.
Here you have to remove the corresponding branches and twigs directly from the trunk. Stumps must not be left behind.
However, cutting the mountain ash has a small disadvantage. If what has faded is removed, no berries follow. A radical sweep is therefore not recommended. Instead, it should only be removed and shortened in a targeted manner.
The growth behavior of the mountain ash
The easy-care properties alone make the mountain ash a plant that is ideal for the garden. And for everyone without a green thumb.
The special behavior during growth is another advantage. The mountain ash grows very quickly at first and immediately reaches a height of one to two meters. After that, however, the increase in size is noticeably reduced. The rowan tree quickly reaches a considerable height, but then maintains it for a long time. This simplifies planning and pruning. In addition, it also ensures that there is neither a forced open area in the garden for a long time nor that it has to be constantly replanted.
The mountain ash can be easily propagated thanks to the bright orange colored fruits. The kernels in these pretty berries are seeds that, when sown, quickly provide for young mountain ash.
But there is one special feature to consider: the pulp.
This contains substances that can prevent or at least delay germination. In the normal case, i.e. naturally, birds eat the berries with their seeds. The pulp is digested and the seeds are freed.
If you want to propagate your own mountain ash, you should proceed in a similar way. True, it is not advisable to consume the berries raw yourself and then wait for the seeds. However, the pulp should be removed. This can be achieved by crushing or slicing. Once the meat has been removed, the kernels are loosened and optionally placed in garden soil or potting soil.
If kept warm, light and moist, they will germinate within a few weeks. A duration of a few months is also possible. The chances of success are greater if the cultivation is done indoors.
When the young plants have reached a height of about 20 cm, they can be put in the garden in spring or in a bucket outdoors. Planting out can also be done in early summer, but the chances of success are poor in autumn because the young shoots then no longer have sufficient time to develop roots and prepare for winter.
Wintering the mountain ash does not require any special preparation or protective measures. The foliage falls off in autumn after a decorative discoloration. The berries are preserved well into winter.
Only young and newly grown shoots should be overwintered in the house. Here they should stand frost-free but cool and light. Occasional watering is also required.
Moving the mountain ash is only necessary if the tree does not thrive in its original location or the area is no longer sufficient.
If the deciduous tree shows only reduced or no growth at its current location, you should first test an increased supply of nutrients through more fertilizer. Often this already makes implementation superfluous. If the lighting conditions are insufficient, for example because another tree is overshadowing the mountain ash or the location is cramped, you should make a change.
Relatively young mountain ash trees, aged three to six years, usually still tolerate this very well. The longer the deciduous tree stood in this place, however, the more difficult the change will be.
In order to protect the plant nonetheless, the largest possible root ball should be cut off. It also helps when sales are prepared. To do this, you should first create a trench around the mountain ash, which you fill with a mixture of loose compost and sand. When poured away, the mountain ash forms fine roots directly in this area, which make it much easier to grow in a new place.
About a year after digging the trench, the rowan tree can be moved relatively safely.
Typical diseases and pests
The mountain ash is a robust tree, but it is susceptible to certain diseases.
Like the fire blight, for example . This disease is transmitted by bacteria and requires immediate removal and destruction of all affected parts. It can then be treated with an appropriate protective agent. At the moment, however, there is still no product specifically geared towards fire blight. Instead, broadband means should be used.
Fire blight shows itself through dark brown or even black discolored flowers and young shoots as well as noticeably dark leaf veins. The discolored parts of the plant do not fall off even in autumn. In this way, the reportable disease spreads to other plants.
In addition to bacterial infection, mountain ash is susceptible to tree fungi, such as the tree sponge or the sulfur sponge. Regular checks and the use of suitable protective equipment help here.
The last disease that can occur is gray mold rot . Here fresh, green and not yet lignified shoots of mountain ash die off and dry up or wither. This can only occur if the location is too humid and the ventilation is insufficient. This is rarely the case in the garden. If it does occur, a fungicide should be used. This usually provides a quick remedy. Removing the affected parts of the plant prevents further spread.
The mountain ash, on the other hand, is very resistant to pests.
Is the rowanberry poisonous?
The fresh, raw fruits of the mountain ash are not poisonous in small quantities. However, if consumed in large numbers, they can cause nausea and vomiting as well as diarrhea. This can be life threatening, especially for children and animals, with the exception of birds.
The situation is different with boiled berries of the mountain ash. These can be safely enjoyed as a dessert, juice or distilled as schnapps. In non-alcoholic form they even have a health-promoting effect, because the fruits contain a lot of vitamin C and other substances that strengthen the immune system, which can prevent a cold, for example.
If you don’t want to eat them yourself, you can leave the berries on the tree. They are a reliable source of food for birds, especially in autumn and winter. However, you should remove grapes that have fallen down when pets or small children are playing in the garden in winter.
The mountain ash is an easy-care and decorative tree that can serve as a feeding place for birds and enrich the garden with an eye-catcher. If used in the right location and with just a few measures, the deciduous tree will flourish for a long time – even if the hobby gardener does not have a green thumb.