Mountain aster, Aster amellus: care from A-Z

Several inflorescences adorn the herbaceous stems of the mountain aster, making the flower one of the most popular autumn bloomers. Bluish violet flowers with a bright, yellow center provide color in the garden bed until the first weeks of October. Unfortunately, the plant that, true to its name, feels at home in mountainous locations, is becoming increasingly rare. It is all the more effective to cultivate Aster amellus in your own garden. If the gardener observes the following care tips, nothing stands in the way of successful husbandry.

Care instructions

Basically, the mountain aster is very easy to care for. Experience has shown that mountain asters develop rather slowly. But once the plant has got used to its location, it impresses with a long-lasting, radiant bloom that the gardener can look forward to every year. However, there are a few factors that he should consider when keeping it.

Location

Stony slopes and many hours of sunshine offer ideal conditions for the perennial. Because of these demands, it is found more often in alpine areas than in flat latitudes. Still, it is possible for anyone with the right care to successfully cultivate the sun worshiper. A gravel or rock garden offers the best conditions. Depending on the variety, the mountain aster can also be kept in the bucket, as it remains relatively low with a height of about half a meter. If the plant threatens to kink - whether in the bucket or in the bed - the plant needs a support.

Mountain stars love it warm and sunny. In the wild they appear in pine forests only in bright places. At times the plant also tolerates penumbra. However, several hours of sunshine a day are essential for healthy development and abundant flowering.

Tip: Pale, undeveloped flowers are a clear indication of a lack of light.

Nevertheless, a location on a south-facing terrace is only recommended with restrictions. It shouldn't get too warm at the location. In this case, the plant becomes susceptible to disease and shortens its flowering period.

The aster spreads independently via offshoots. If it feels comfortable in its location, the flower will multiply quickly and extensively.

floor

Bergastern have few demands on a well-kept floor. They also grow in places where other flowering plants are far too dry and rocky. The earth should still provide many nutrients. Otherwise it is satisfied with a dry, loamy-sandy substrate. The gardener ideally lays out the bed with gravel or stones. It is only important that the soil is well drained. The mountain aster does not tolerate waterlogging. Particularly when keeping the bucket, it is important to ensure that rain and irrigation water can drain off without any problems. A layer of gravel is suitable here in two ways. On the one hand, the gardener creates the best site conditions, as stony soil meets the natural requirements of the aster. On the other hand, gravel is a great way to lay drainage.

Note: The loamy soil requirements of the plant, on the other hand, can be fatal. Loamy soil is naturally dense and impermeable.

Instructions - create drainage in the flowerbed

• Dig up the soil down to the deep layers
• Mix the excavated material with sand
• Work soil into the hole again
• do not knock or tamp down

Limescale

In addition, the mountain aster has a particular preference for calcareous soils. This property also earned it its nickname lime aster. In order to create the optimal site conditions, it is advisable to first check the lime content of the soil with a test strip from the hardware store. If the result shows that the pH value is too acidic, the gardener limes the soil as follows:

• Clay soils at a pH of 7
• sandy loam soils with a pH of 6.5
• sandy soils with a pH of 5.5

If these values ​​deviate slightly, it is sufficient to work around 150 g of lime per square meter into the soil every three years. If the values ​​do not improve or if they are well below the recommended value, the gardener increases the amount to 250 g per square meter.

The best time to limewash the soil is in spring. On a dry day, the gardener works the remedy deep into the earth. It is important that the soil is dry for this. Alternatively, this can also be done in autumn.

• Humic soil: carbonate or algae lime
• Heavy clay soil: quicklime
• Light to medium soil: garden lime
• Alternatively: rock flour

plants

Basically, the gardener can plant young plants in the ground all year round. The only exclusion criterion is frozen ground. However, spring is recommended, when the foliage has already fallen and has not yet formed again.

instructions

• Loosen the soil / incorporate drainage
• Maintain a distance of 40 to 50 cm
• Put 4 to 6 plants per square meter
• Do not plant Bergastern from the trade any deeper than the existing pot

Tip: Bergastern are not only an eye-catcher in the bed, they are also ideal for framing beds. Still, the gardener shouldn't plant them too densely for this purpose either. Aster amellus spreads quickly and, with good care, grows tightly together over time.

Suitable plant partners

• Goldenrod
• sunflowers
• Grasses
• Sun eye
• Sun bride
• Sun hat
• Splendid notch
• Monard
• phlox
• Agastache
• Gold or silver thistle

to water

Since aster amellus thrives on dry soils, normal rainfall is sufficient as irrigation water. The gardener only has to give their water additional water in the event of prolonged drought.

Tip: In summer, water should be given in the early morning or late evening hours, if possible, to prevent burns from intense sunlight.

Fertilize

Asters enjoy being fertilized twice a year. In the case of the mountain aster, it is advisable to enrich the substrate, especially in the first year of standing. A long-acting perennial fertilizer is suitable. Experience has shown that this care measure leads to a richer flower development.

Cut

The gardener has to cut back the mountain aster annually so that many violet flowers also form in the following year. The pruning instructions provide for this measure for autumn or after flowering. He should also rejuvenate the plant every three to four years. He removes all old and lignified parts of the plant.

Note: Gardening advisors often advise not to prune asters before the onset of winter. In the case of the mountain aster, however, pruning close to the ground in autumn is not a problem. While the shoots of other species represent an important protection against frost, the mountain aster is winter-proof.

Multiply

Anyone who does not want to leave Aster amellus to its own devices to spread, but rather wants to multiply the flower in a targeted manner, can achieve this by dividing it. Otherwise, the plant will form runners and occasionally appear in undesirable places in the garden. The best time to split is in spring or the post-flowering period. Ideally, the division takes place every two to three years to rejuvenate the plant.

• Dig up mountain aster
• Separate the root ball with a spade depending on its size
• or pull it apart with your hands
• Plant sections with two to three eyes in a new location
• Check the original root ball for bald spots
• Do not plant them again, but dispose of them on the compost

Note: Division is the simplest method of reproduction. If desired, the gardener can also multiply his plant by sowing or cuttings.

Overwinter

In contrast to many other aster species, the Aster amellus variety is hardy. It can withstand temperatures from -23 ° C to -28 ° C. If you want to be on the safe side, cover the root ball with some leaves. Particularly in the case of buckets in which the substrate freezes quickly, a precautionary maintenance measure cannot do any harm.

Diseases and pests

Inconsistent site conditions increase the mountain aster's susceptibility to pests. A lack of light, in particular, often leads to disease.

Too dense growth causes powdery mildew, for example. The parasite manifests itself in a white coating on the leaves. However, the pests mostly sit on the underside of the leaves. In the case of a slight infestation, it is sufficient to wipe this covering with a cloth and change the location. In the long term, the plant can be treated with plant broths made from field horsetail or milk. Beneficial organisms such as ladybirds also fight the fair and bad weather fungus in a biological way.

Also feared is the aster wilt, in which the leaves hang limply as if the flower had dried up. In this case, the gardener will transplant the crop and replace it with a sturdy plant. He is only allowed to plant an aster again in the same location after at least four years.

Failure to follow the correct care instructions sometimes leads to balding of the mountain aster. Insufficient nutrients are then the cause. With a little compost or other organic fertilizer, the unsightly look is quickly remedied.

Popular varieties

• Aster pyrenaeus 'Lutetia'
• Aster amellus' Dr. Otto Petscheck ‘
• 'Lucky find'
• 'Pink Fulfillment'
• 'Rudolf Goethe'
• 'Star Ball'
• 'Ultramarine'
• 'Violet Queen'