Asters - Annuals of Many Colors

In short: China aster (Callistephus chinensis) is a frost-sensitive annual sown from late February through March and flowering from summer until the first frosts. Varieties fall into three height groups: tall 50 to 70 cm for beds and cutting, medium 30 to 50 cm, and low around 25 cm for pots and window boxes.

China aster (lat. Callistephus chinensis) is an annual from the Asteraceae family. Its homeland is Asia, specifically China. Currently, aster cultivation has become widespread. Thanks to breeding, asters are very diverse and will brighten up any flower bed. The original asters had simple daisy-like flowers; the first double-flowered varieties were bred only in the mid-18th century. Since then, countless shapes and colours of these plant flowers have been bred. Today, asters are divided into groups according to height: tall ones reaching approximately 50 – 70 cm, medium ones reaching 30 – 50 cm, and low ones reaching around 25 cm. According to the shape of flower heads, asters are divided into daisy-flowered, peony-flowered, chrysanthemum-flowered, pompon-flowered, and needle-shaped types. Domestic achievements are also evident in aster breeding. After World War II, the Research Institute of Ornamental Horticulture in Průhonice succeeded in breeding the cultivar Průhonický trpaslík (Průhonice Dwarf), which are low asters with small flowers in many colour variations.

Choose Whatever You Like – The Selection is Diverse...

• Chrysanthemum-flowered asters grow into bushes that are suitable both for planting in flower beds and in pots. Flower colors can be varied – white, pink, purple...

• A representative of peony-flowered asters is, for example, Emilka, which has purple double flowers and grows to a height of approximately 70 cm. It is grown in flower beds and is suitable for cutting. Junona is also a peony-flowered aster, with a delicate yellow flower color. Peony-flowered asters are also available in pink.

• The flowers of pompon-type asters are very interesting. They grow up to 70 cm tall, making them more suitable for growing in flower beds and for cutting. Flower colors include cherry red and yellow. Two-toned pompon asters grow to approximately 60 cm. The combination of a white center and red edge catches the eye immediately, as does the white-purple combination.

• Single-flowered asters resemble colorful daisies. While the flowers aren't large, they certainly have their admirers. The color range is truly wide.

• Hi-no-maru is the name of an aster cultivar that grows only 20 – 25 cm tall, with abundant flowering, a pink center, and white petal edges. Thanks to its low growth, it's suitable for both window boxes and flower beds.

• Needle-type asters grow to a height of approximately 50 – 60 cm, are mostly grown in flower beds, and are suitable for cutting. They are available in carmine red, purple, blue, pink, yellow, and white. Those who want a multicolored flower bed can choose a color mix.

• Průhonický trpaslík is a purely Czech cultivar that is very popular among growers. The plants are smaller in stature, with smaller, double flowers. Průhonický trpaslík is suitable for growing in both flower beds and pots. It stands out when planted in larger areas. It can delight the eye in a delicate light pink color. The most recently bred cultivar is the yellow-flowered variety. For lovers of diverse plantings, a mix of white, pink, scarlet, and blue flowering plants is available.

With Chinese asters you say: "I'm dying of jealousy at your feet"

Growing Asters

Asters thrive in bright, sunny locations. The soil should be well-drained and rather calcareous. Asters do not tolerate direct fertilization with farmyard manure, so it's better to use finely chopped grass and leaves for autumn fertilization. Tall asters should be grown in sheltered locations to prevent heavy flowers from breaking under wind pressure. Tall and medium-height varieties are suitable for growing in beds and for cutting. Low-growing varieties are ideal for planting in containers. Asters bloom from summer until approximately September or until the first frosts. Asters are not frost-resistant, so if you want to enjoy their flowers longer, cover them with non-woven fabric before the first frosts arrive.

Tip: Always cut asters for vases in the evening – they'll last longer.

Asters are grown from seeds. You can pre-grow seedlings, or in warmer areas, sow directly into the bed. Seed sowing is carried out as early as late February and throughout March so that young plants develop sufficiently before planting in their final location. To prevent young plants from being attacked by molds and pests, it's advisable to use sterilized substrate and disinfected seed trays or pots. Sowing should not be too dense to avoid exhausting the plants. If you've sown asters in a tray, you must prick them out. Be careful not to damage the young seedlings during this process – they are very delicate. Once mature, seedlings can be planted out in the bed after the last frost. Regularly water and hoe the aster bed. Always water in the evening when the sun is no longer shining on the asters and the temperature has dropped slightly. Watering on a hot day could lead to the formation of unsightly dark spots on the leaves.

Fusarium – The Bane of Asters

Fusarium are fungi that attack asters. These fungi are very insidious. After infection, mature plants suddenly begin to wilt and subsequently die. Once infected, there is no help for the plant. Remove dead asters as soon as possible. Never put them in compost – the best solution is to burn infected plants, as high temperatures destroy the fungal spores. The best protection is not to plant asters in the same location and to carry out preventive chemical spraying. Previcur has proven effective – it's applied before sowing as soil disinfection and then after planting in the bed. Other sprays designed for crown rot can also be used.

Important rule: When growing asters, regular annual crop rotation is essential!