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Due to the variety of colors, the duration of the flowering period and undemanding care, the perennial herbaceous plant astilba is very popular among summer residents. Today we will tell you how the astilbe is prepared for winter.
Autumn procedures
By its nature, the astilba ornamental shrub is hardy and frost-resistant, so the plant can be cultivated in various climatic zones. In order for a perennial to successfully winter, you need to know how to properly prepare it for wintering. According to experienced gardeners, there is no single scheme for preparing and warming ornamental plants. Astilba shelter for the winter in the Moscow region, Krasnodar, the Volga region or the Urals has significant differences.
So, the preparation of the perennial for the upcoming cold weather begins in early autumn. First, the territory of the garden plot is removed from branches broken by the wind, fallen leaves, dry tops and other vegetation. Dry leaves and tops can be sent to a composter for humus. Removing weed grass, loosening the soil in the near-trunk circle and water-charging watering provide the necessary oxygen access to the roots of plants growing in the garden.
Video: “Technology of autumn pruning of astilba”
From this video you will learn how to prepare and insulate a perennial shrub for the winter.
Trimming
Autumn is the season for trimming ornamental shrubs. At the same time, the timing of pruning depends on the cultivated perennial variety and its growing zone. Early varieties of astilba bloom at the very beginning of summer, later ones – closer to the end of the growing season. In the southern regions, the pruning procedure falls at the end of October or the beginning of November, in the northern regions – at the last decade of September.
At the end of flowering, dry flower stalks remain on the shrub. Some novice gardeners are wondering if dried flowers need to be pruned or if they can be left until spring. The presence of dry branches does not prevent the plant from growing and developing, but the decorative culture loses its attractiveness. Removing dried flowers allows you to more accurately and competently insulate the shrub for the winter. In order for the astilbe bush to be insulated for the winter, it is necessary to cut off the old shoots damaged by the wind and harmful insects, and also remove the dry inflorescences. Astilba shoots need to be cut almost to the very root. The distance from the cut to the matured wood should be at least 2–3 cm.
Mulching
Immediately after the sanitary pruning of the crown, the root system and young shoots are mulched. Young shrubs are insulated with peat, sawdust, tree bark, straw, small spruce twigs, hay, dry earth and sand. For soil mulch in the trunk circle, you can use trimmings of covering material and pieces of cardboard. Perennials aged 1 to 5 years are covered with a layer of mulch 5–7 cm high.
Plants aged 5 years and older, the root system of which has grown so much that it began to break through to the top, need more thorough shelter. The height of the mulching layer should be at least 20–25 cm. From above, the shrubs are covered with pine spruce branches or non-woven covering material.
Fertilizer
Astilba belongs to plants that are unpretentious to growing conditions, however, top dressing with potassium-phosphorus fertilizers helps to strengthen the root system of the perennial. With the advent of autumn, it is recommended to abandon nitrogen-containing fertilizers, which give enhanced growth and development of ornamental plants.
Closer to mid-autumn, adult shrubs are fed with organic matter. Organic type fertilizers decompose very slowly. Accordingly, astilba will begin to use them as an additional source of nutrition only with the onset of spring heat.
winter shelter
Now let’s figure out whether it is necessary to cover astilba for the winter. A perennial shrub with high frost resistance. Therefore, in regions where there is a lot of snow and there are no severe frosts, no special shelter is required for this ornamental crop. According to the recommendations of experienced gardeners, the shrub should be mulched with peat, tree bark and sawdust, hay, straw, dry foliage and earth. The mulching layer should completely cover the root system of the perennial and its shoots, the length of which after pruning reaches only 5–10 cm.
Plants aged 5 years and older are additionally insulated with pine spruce branches, lutrasil, agrofibre, geotextile fabric and other non-woven covering materials. This procedure is necessary in order to prevent freezing of the rhizome protruding above the ground, as well as to protect plants from glaciation during an unforeseen thaw. In severe frosts, it is recommended to make an additional frame fence made of wooden boards, inside which you can pour dry earth and leaves fallen from trees.
Regional Distinctive Features
The technology of preparation and shelter for the winter of fruit and ornamental crops depends on the characteristics of the climatic zone. If you do not properly prepare for wintering, you can destroy the plants growing in the garden with your own hands.
Astilba bushes growing in the south of the country do not need to be covered. Mild and warm winter, which is typical for the Crimea, Kuban, Stavropol Territory, Adygea and Krasnodar Territory, is not terrible for astilba. In order for an ornamental perennial shrub to successfully winter, you need to properly mulch its rhizome and cut shoots.
The middle zone of Our Country is characterized by sharp temperature changes. An unexpected thaw can be replaced by a sharp cold snap and severe frosts. The water accumulated in the ground freezes, which leads to glaciation of the astilba root. Ornamental shrubs cultivated in the Moscow region and other central regions of the country are insulated with any non-woven material.
As for the Urals, Siberia and other northern regions, astilbe bushes are recommended to be additionally insulated with pine spruce branches, slate or roofing material. Make sure that moisture does not begin to collect inside the protective structure, otherwise the plants may die.
Common mistakes
Due to their inexperience, novice gardeners often make typical mistakes when preparing plants for wintering. So, covering astilba with plastic wrap can lead to the appearance of mold and fungal spores on the rhizome of the shrub. To avoid the death of a decorative perennial, you should choose the right covering material.
If it was not possible to find an alternative to polyethylene, it is recommended to make small holes in the film, which will act as special dies for air exchange.
Incorrectly selected fertilizers and a violation of the technology of their introduction into the soil lead to the withering of the plant. Too late or, conversely, early pruning of shoots and dry inflorescences is one of the main reasons for freezing astilba in winter. A plant weakened after pruning does not have time to get stronger and gain strength before the first frost.