These are perennial herbaceous plants originating in Asia; generally they grow 30-40 cm in height, but there are dwarf species and even larger species, up to 100-120 cm. They consist of dense, roundish bushes, consisting of thin stems with generally composed leaves, similar to ferns, pointed and serrated, of dark green color; some species have bronze or reddish leaves. From June to the end of summer they produce long erect inflorescences, sometimes arched, higher than the bush, pyramidal in shape and with a feathery and soft appearance: they are made up of innumerable small flowers, red, cream, white, pink or lilac. There are numerous hybrids of astilbe, selected for the color of the flowers or for the decorative leaves.
the astilbe they are grown in a semi-shaded place, where they can enjoy a few hours of sunshine during the cooler periods of the day; these plants can be planted even in full sun, but in this case they need continuous watering, or to be placed near water gardens because otherwise direct sunlight could cause serious damage. The astilbe they grow without problems even in complete shade, in this case, however, their flowering will be very poor.
They are plants that do not fear the cold and can also withstand temperatures close to -20 ° C, they fear the heat much more, and in the summer months they should be shaded, if placed in full sun to avoid direct sunlight during the of the hottest hours of the day can cause even very serious damage.
These plants need abundant and regular watering, in order to constantly leave the soil slightly humid, watering should be intensified in the hottest and dry months of the year, especially if the plants are exposed to many hours of sunshine.
In winter, avoid watering. From the beginning of spring supply fertilizer for flowering plants every 8-10 days, mixed with the water of the waterings so as to obtain more vigorous and lasting blooms.
These plants are rather rustic and can adapt to different types of soil even if, for optimal development, the astilbe like soft, well-drained, loose and rich in organic matter soils; love slightly acid and possibly moist soils.
They are plants of easy cultivation having a rustic character that allows their cultivation even in not particularly suitable grounds, even if, in this case, their growth will be limited.
The reproduction of this genus of plants usually takes place by seed in spring; in the autumn season and at the end of winter it is possible to divide the clumps of leaves, so as to leave some vigorous roots for each portion practiced, the new plants thus obtained should be immediately placed in a soft and well-drained soil to allow their engraftment.
Astilbe: Pests and diseases
occasionally the inflorescences are attacked by the aphids, even if in general the astilbe being rustic and rather resistant, they show signs of suffering only for the heat of days with high temperatures or drought, being a variety that requires regular watering.