American asters in garden design - types and varieties, care
Asters blooming in summer and autumn are absolute favorites both among amateur gardeners and professional designers. True, the attention and admiration attract, most often, the bright Euro-Asian asters. Lush flowering and outstanding endurance (though not always), along with an easily recognizable appearance, make them all the more popular. But North American asters, also blooming in the summer-autumn period, are not familiar to everyone. With the exception of two dominant species - asters of New England and New Belgian. Unpretentious, not quite ordinary and very luxuriantly blooming symphiotrichums, or American asters are able to expand the palette of garden asters with new colors.
Description of American Asters
The selection of a number of species among asters as a separate mixed group of summer-autumn flowering is not accidental. There were many confusions caused by the exact distribution of asters to either summer species or autumn stars. Indeed, many summer asters bloom so late or bloom so long that they capture the beginning of autumn, actually mixing the two groups together.
And the allocation of two subgroups within the framework of summer-autumn asters is easily explainable and indisputable: beloved and popular Euro-Asian species and much more rare North American species differ significantly not only in flowering.
Changes in the classification of asters in the group of North American species affected the most. Almost all American plants, as part of a huge community of plant species of the family Asteraceae, were transferred from the genus Astra to the genus Symphyotrichum. Changing the official botanical name has little effect on the practical nuances of using and growing these types of asters, but it fully corresponds to their status as special plants.
American Asters, North American Asters, or Symphiotrichums - flowering varieties of herbaceous perennials and shrubs. Symphiotrichums got their name from the Greek concepts of "merge" and "hair". These asters are not called American by chance: in nature they are found only on the American continents (with rare exceptions), their distribution area is almost always limited to North America.
Symphiotrichums are herbaceous perennials with strong, straight, branching shoots that form wide and very stable bushes. The average height of plants varies from 70 cm to more than 1 m. As a rule, North American asters have regularly arranged, lanceolate, saturated-colored leaves.
Most American asters are small-flowered, with a basket diameter of 1 to 3 cm, although the best varietal asters please with much more catchy inflorescences. But dozens of their baskets are collected in shields and brushes of complex inflorescences. The palette of colors with delicate, pure shades of lilac-lilac-white tones is inimitable.
The flowering period of American asters begins in June and ends only with the advent of winter. Many of the most valuable species bloom only in September.
North American species of summer-autumn asters
Symphiotrichum - plants are quite diverse, although often the differences in their appearance come down to the color of inflorescences and the structure of the bushes. The genus Symphiotrichum includes more than 100 plant species. Despite the fact that almost all the representatives bloom beautifully and can be used as a garden culture, only less than ten types of American asters have become popular, which are actively used by breeders to breed interesting new varieties.
Two types of American asters have become a true legend in landscape design. They were introduced into the culture after the Italian and Alpine asters, for more than four centuries paying tribute to their amazing stamina. Among the absolute favorites among American asters rightly ranked:
- Symphiotrichum New English, or Astra New English (also known as american aster, Symphyotrichum novae-angliae) Is a legendary, almost historical species of asters and one of the most popular plants. At a height of up to 2 m, it conquers in a sweep of dense, sprawling, often sloppy bushes from branching, straight, densely pubescent shoots.
Lanceolate leaves do not create an impressively dense crown, but magnificently emphasize the beauty of flowering. With a diameter of up to 4 cm, the baskets of New England Aster inflorescences are surprisingly saturated in the tone of pink-lilac-lilac reed flowers, yellow or reddish-brown tubular in the center.
This aster always blooms one of the last. In September and October, letting out up to 30 inflorescences on a bush, it stays firmly in any weather and pleases literally before the arrival of winter, withstanding even weak morning frosts.
Varieties of New England asters are more lush, relatively compact plants with improved leafiness and, as a rule, larger inflorescences. The choice is best made by the color of the inflorescences and the shape of the bush. The best for the middle strip are considered varieties Gerberose, Lille fardell, Septemberrubin, Bars pink, Gloire de kronstadt, Constance and etc.
- Symphiotrichum virgin, or Astra virgin (also known as Astra New Belgian (Symphyotrichum novi-belgii, Michaelmas Daisy) - a changeable, very plastic look, which is easily recognizable by the shape of the crown - back conical, expanding upward. Depending on the variety, the height of the bushes ranges from 0.5 to 1.5 m. The shoots are straight, begin to branch out densely in the upper part, which gives the bushes a bouquet-like shape.
Thick leafyness makes this aster very elegant. Typical linear, narrow leaves are usually colored in a dark tone. On one bush, up to several dozen complex panicles or inflorescence brushes can bloom, each of which consists of more than a hundred baskets.
Inflorescences-baskets of New Belgian symphiotrichum are limited to 2 cm in diameter, numerous reed flowers are painted in different shades of lilac, completely hide the tubular flowers in the center. These are plentiful-colored and very spectacular terry asters, which begin to bloom in September.
Virginia's symphiotrichum is characterized by the most extensive selection of varieties. Various shades of color, height, degree of terry allow you to select more catchy or, conversely, modest plants. The most popular varieties for the middle band are considered meter-tall varieties Saturn, Amethyst, Octoberfest, Royal blue, Sunset and Ballard.
The best representatives of the genus Symphiotrichum also include:
- Symphiotrichum shrubby, or Astra shrubby (Symphyotrichum dumosum) - a fairly compact form, forming bushes similar to pillows about half a meter high. In the West, this type of symphiotrichum is also known as dwarf new belgian asters (Dwarf novi-belgii asters, Mini Michaelmas daisies).
Direct shoots densely branch, pubescent, and sessile leaves are solid and dark. The diameter of the inflorescence baskets of this aster is also limited to only 3 cm, but flowering seems more spectacular due to the fact that individual inflorescences are collected in sparse shields. The light lilac color of small and narrow reed flowers contrasts pleasantly with dark dense greens. This is an abundantly blooming type of aster, which in August and September is literally covered with a scattering of baskets.
Numerous varieties of shrubby aster offer a choice of more compact, 25 cm tall bushes with different variations of blue, lilac purple and pink colors (for example, medium-sized pink-colored Diana, dwarf fuchsia variety Venuslilac dwarf Dwarf nancy, snow-white variety with a height of about 30 cm Niobea etc.) Varietal plants are considered more resistant.
Symphiotrichum heather, or Astra heather (Symphyotrichum ericoides) - a herbaceous perennial up to 1 m high with straight shoots, fancifully branching on thin long bushes, due to which the plant acquires a resemblance to heathers.
The leaves are small, linear, arranged alternately and stand out with their rather bright color. Despite the fact that the diameter of the inflorescences is limited to a maximum of 1 cm, they do not seem inconspicuous. In a huge number of snow-white baskets strew the plant, resembling a fairy tale placer or lace. This is one of the most late-blooming asters, starting its show only in September.
Symphiotrichum hearty, or Astra hearty (Symphyotrichum cordifolium, also known as blue forest aster) - the plant is surprisingly tender and variable. In height, it can be limited to 60-70 cm, and stretch to more than 1 m. None of the other asters have stems that branch so densely. The reddish color of the shoots emphasizes the beauty of the dark, with an unusual rough texture, oval, with a heart-shaped base of leaves.
Thicken, spreading, multi-tiered panicles of inflorescences consist of small baskets with a diameter of up to 2 cm, with strongly pointed reed flowers. The contrast of light pink, purple or white with a yellow center seems surprisingly bright. This is a late blooming aster that attracts its eyes in September and October.
- Symphiotrichum widespread, or Astra widespread (synonym - symphiotrichum corymbose, Symphyotrichum divaricatum) Is a compact, but very effective form of symphiotrichum. This plant conquers with lace textures. At a height of up to 75 cm, the bushes are very sparse, dense, and small oval leaves on long stalks give the plant the effect of green lace.
Baskets of inflorescences with a diameter of about 3 cm surprise with a contrast of white reed and brown tubular flowers. Inflorescences are collected in loose shields towering above the greenery. This is a late-flowering type of aster, blooming only in September and pleasing to the very frosts.
- Symphiotrichum crimson, or Astra crimson (Symphyotrichum puniceum) - a tall, magnificent view of asters with branched straight shoots and surprisingly dense foliage, creating the effect of green lace. At a height of about 120 cm, this type of symphiotrichum boasts a unique purple-crimson shade of reed flowers around a lemon center made of tubular in inflorescences, the diameter of which exceeds 2.5 cm.This species blooms in mid-summer, when weather is favorable, it always pleases with repeated flowering in autumn.
- Symphiotrichum naked, or Astra nude (Symphyotrichum laeve) - medium, very strong appearance with a height of 70 to 120 cm, depending on the fertility of the soil. Strong, tough and straight shoots beautifully branch, flaunting with next lanceolate leaves with an almost imperceptibly serrated edge. Baskets of inflorescences up to 3 cm in diameter are surprised by the tenderness of a lilac tone and the bright pink-purple color of the tubular flowers in the center. This is a blooming species exactly in the middle of summer that pleases all of July.
American asters in garden design
All types of symphiotrichum are considered one of the best asters for group plantings. In mixed compositions, especially in a natural style, they demonstrate unique skills to merge into harmonious, “solid” ensembles with any neighboring plants. These types of asters do not look too neat, but their splendor, picturesqueness and brightness, as well as late flowering, fully compensate for this shortcoming.
American asters look great:
- in arrays and imitations of wild prairies;
- in landscape continuous plantings and natural flower beds or mixborders;
- when planting in narrow flower beds-ribbons;
- large and medium-sized groups on a lawn or meadow from groundcover;
- as a masking tape and border culture;
- in bright texture accents, when making large and lush plants with an unusual bush shape (especially small-flowered species like heather symphiotrichum);
- at the edge and the creation of an understory framing large plants.
The group talents of this plant do not at all mean that in proud solitude the symphiotrichums will be lost. They can be safely entered as single accents and even placed as a solo plant on the lawn. As an autumn accent, they perfectly fit into any complex ensembles - both ceremonial and functional.
American asters are superbly cut-resistant. For autumn bouquets, high grades of New English and New Belgian symphiotrichums are most often used.
Partners for American asters are bright, seasonal and “reliable” plants, they blend perfectly with partner perennials, crops with vertical or racemose inflorescences, as well as perennials that fit well into landscape ensembles. Asters of North American origin can suppress slightly competitive plants, so partners for mixed compositions are carefully selected, mixing them only with perennials and shrubs that can stand up for themselves.
Symphiotrichum - plants are not capricious and, as a rule, adapt perfectly to growing conditions. But the minimum requirements for selecting sites in the garden for these types of asters should be followed quite strictly. These are light-loving and drought-tolerant plants that are afraid of excess waterlogging.
For symphiotrichums only places with good lighting are suitable. In regions with severe winters and for all large-flowered plants, sunny areas are preferred. Too hot places, southern slopes are best avoided, but you should always choose the brightest of all possible options.
High, from 1 m in height, the types and varieties of American asters are best placed on windproof areas, medium-tall and low symphiotrichums are stable even in open areas.
For all, without exception, symphiotrichums, fertile, high-quality, loose soils with a minimal risk of waterlogging are preferred. On poor soil, symphiotrichums bloom sparingly, but survive. Small-flowered heather aster prefers dry soils. All other American species are slightly moist, fresh, but not moist soils (the aster shrubbery is especially afraid of very dry soil).
For a New England and New Belgian aster, before presowing treatment, it is advisable to add organic and complete mineral fertilizers to the soil (1 bucket of organic per square meter and 50-60 g of mineral mixtures). For the rest of the asters, you can restrict yourself to a simple digging.
There is nothing complicated in planting a plant. The main thing is to avoid thickening and excessive crowding when placing plants. Planting asters of North American origin, as a rule, is carried out in individual pits, similar to the diameter of the root coma of seedlings. Landing distances are 35-40 cm for asters up to 70 cm high and 45-50 cm for tall species and varieties. Landing of American asters can be carried out both in the spring, in late April-early May, and in early autumn, in the third decade of August or the first half of September.
American asters, unfortunately, rarely boast longevity. So that the bottoms of the bushes do not expose, maintain a beautiful shape, delight not only with flowering, but also with greenery, it is advisable to separate these plants every 3-5 years. For magnificently growing asters, this is the only way to avoid unnecessarily densifying plantings (for example, for New England aster). You can focus on the need for separation both by deteriorating plant growth or poor wintering, and by reducing the number of inflorescences.
Caring for American Asters
The drought tolerance of all American asters greatly facilitates the process of growing plants. As a rule, any representatives of symphiotrichum, with the exception of freshly planted and young plants, do not need watering.Only shrub symphiotrichum requires mandatory watering in a drought, but only at the budding stage and in the first half of flowering. Asters are afraid of watering with cold water.
Critical for American asters is only top dressing during budding or at the beginning of flowering - phosphorus or phosphorus-potassium fertilizers. For all types of symphiotrichums, except shrubbery, one can limit oneself to early spring top dressing with full mineral fertilizers and flowering stimulating top dressing at the budding stage.
Symphiotrichum shrub prefers 3-4 dressings per season to obtain the most magnificent flowering. New England asters are fed 2-3 times a year, in spring and potassium-phosphorus fertilizers with full mineral fertilizers - before and during flowering.
For all abundantly flowering asters, it is important to maintain the soil in a loose state, during weeding renewing its water permeability and preventing the formation of soil crust.
Pruning on American asters is reduced to cutting to short stumps of last year's shoots. Traditionally, pruning is carried out in the spring, although if desired, it can be shifted to the fall.
Symphiotrichums are vulnerable to powdery mildew and various fungal diseases, especially in a weakened state. The older the plant becomes, especially in the absence of regular division, the higher the risk of infection.
Wintering North American asters, as a rule, is not difficult. Plants are considered one of the most hardy and tolerate conditions not only of the middle band. The only difficulty is that with age the plant rises, forming a kind of hummock.
Therefore, with signs of aging, the risk of freezing of uplifted young shoots, they either rejuvenate by separation, or regularly pour soil before the winter and mulch the base of the bushes to protect the rhizome.
Breeding american asters
The main method of propagation of any symphiotrichum is separation. Since the bushes tend to rise above the soil, regular division is carried out often enough, which allows you to constantly increase the collection.
It is possible to dig out small parts of bushes without digging the main plant, rooting miniature dividers with 2-5 stems and separating only young parts. In regions with severe winters, the separation of asters is best done only in the spring.
If desired, you can get new bushes and cuttings. Symphiotrichums use apical cuttings from green and semi-lignified shoots. Root branches under the hood, in greenhouses or containers.
Some types of American asters can be grown from seeds. Sowing on seedlings or on individual seedling beds is preferred.