Dahlia (lat. Dáhlia) or Dahlia is a perennial flower of the Astrov family. This family also includes marigolds, gerberas, chrysanthemums and other flowers. Dahlias naturally grow in the mountainous regions of Guatemala, Mexico and Colombia.
In the genus, according to various sources, there are from 4 to 24 species, and the height of wild dahlias reaches 5-6 meters.
In cultural horticulture, the most common type of Dahlia changeable (Dahlia variabilis) or Cultural Dahlia (Dahlia cultorum). Currently, about 15-16 thousand varieties of these beautiful flowers are known.
Dahlia is a perennial plant that grows but does not hibernate outdoors. The upper part of the stems with leaves dies off by winter, and the lower part with tuberous roots (tubers) remains. During growth (vegetation), the lower part of the stems stiffens, and the tubers accumulate nutrients for wintering and further development of the plant.
Types of dahlias. The American community of dahlias lovers has identified 18 species for themselves, which differ in size and flower shape. Among them: lace dahlias, anemones, single dahlias, decorative, spherical dahlias, water lilies and others.
The international classification includes 10 species, differing in the size of the bushes, the shape and color of the flowers:
Soviet breeders assigned all of the above species to two groups: double and non-double.
The color of the dahlia is very diverse and has 15 colors and shades: white, yellow, lavender, orange, pink and dark pink, red and dark red, there are two-color and variegated varieties.
Popular varieties of dahlia:
"Akita" (Akita) - cactus variety of dahlia. Bred in Japan in 1978. Height 70-100 cm, diameter of inflorescence 20-25 cm. One of the most spectacular varieties, color - red-yellow.
"Baywatch" - anemone variety. Bred in the Netherlands in 2005. Height 90-110 cm, flower diameter 7-10 cm, pink-violet color.
"Dutsn explosion" - semi-cactus or decorative variety. Released in 1994. Height 70-90 cm, diameter of inflorescence 10-15 cm.
"Ezau" is an ornamental variety of dahlia. Bred in the Netherlands in 1970. Height 100-110 cm, characterized by large flowers (25-28 cm) yellow-lemon color.
"Figaro" - a variety of dahlias of the class transitional or changeable. Height 60-70 cm, pink flowers, diameter 12-15 cm.
"Fire and Ice" - decorative variety with semi-double flowers, white in bright red stripes.
"Holland Festivale" is also an ornamental variety with pastel orange flowers.
"Giraffe" - orchid variety with yellow reed petals with raspberry stripes.
"Jamaica" is an ornamental variety. Height 60-70 cm, red-white flowers, diameter 8-10 cm.
"Pink Giraffe" - orchid variety with pink reed petals.
"Smokki" - decorative spectacular variety of lilac dahlia with dark purple shading.
Location and landing. Dahlias look great in mixborders. In this case, undersized varieties are planted in the foreground, and tall ones in the background. Since there are so many different colors of dahlia, the flower garden can be decorated in any color scheme, depending on its style. Low-growing dahlias are used to decorate borders or arrays. Abundantly flowering or large-flowered varieties are good in single plantings against the background of the lawn.
Heat-loving varieties of dahlias need sunny, protected from the cold wind, areas. The planting site must be drained, since the tubers of plants do not like stagnant water. Dahlias grow poorly in lowlands and wetlands.
Dahlias prefer nutritious, non-heavy soils. Rotted manure can be added to poor soil. If the soil is too alkaline, it should be acidified with peat, if it is too acidic, lime or ash is added to the soil.
Planting in open ground is planned when the ground warms up well, depending on climatic conditions - from late April to early June. In the fall, the site must be dug up, and in the spring it must be dug again. Two weeks before planting, the tubers are germinated and divided, 2-3 buds are left on the cuttings.
Depending on the variety, the depth of the planting pit varies from 15 to 30 cm. Tubers are laid on the bottom of the holes with sprouts up, watered abundantly and covered with prepared soil mixture or soil. It is necessary to ensure that the upper sprout is at a depth of 3-5 cm. The soil at the site of the planting pit is mulched with humus or peat to protect it from weeds and reduce the frequency of watering.
The distance between plants depends on their variety and the height of future bushes and can range from 50-60 cm for low-growing ones, up to 80-100 cm for tall dahlias. When planting near each bush, you need to drive in a peg-support for further garter. Support is especially needed for high grades.
Dahlias - Care from spring to autumn
Watering. Dahlias need regular watering, in dry and hot weather, and immediately after planting - daily to keep the soil under the plants constantly moist. In the future, watering can be done less often - 1-2 times a week. Since September, watering is stopped.
Loosening, mulching, hilling. In order for the soil to lose less moisture, when planting, the land is mulched with peat or humus. After watering, the soil near the dahlia is loosened and weeds are removed. It is better to get rid of them by hand so as not to damage the root tubers of the plants.
When the bushes grow 10-15 cm, they need to be spud. In the future, it is advisable to repeat the procedure 2-3 times, this will improve the formation of tubers and increase the resistance of plants.
Top dressing. As a rule, dahlias are not fed, they grow well without fertilization, but for a more luxuriant flowering, you can also fertilize. If humus was introduced when planting the dahlia, the bushes begin to feed no earlier than a month later.
Any fertilizer is applied immediately after watering. Of the organic, humus or mullein is used strongly diluted in water. Organics give a long lasting effect, so you can apply top dressing at intervals of 1-2 months. Complex minerals are applied during the growing season with an interval of 1 month. In the second half of August, all feeding is stopped.
Trimming and shaping. For earlier flowering, pinching is carried out - lateral shoots (stepsons) that grow in the leaf axils are removed. Dahlias grown from tubers leave the two strongest shoots, the rest are removed as early as possible. In cuttings, one shoot is usually left.
In tall varieties, the lower leaves are cut off to a height of 30-40 cm for better ventilation of the bush. Low-growing (dwarf), small-flowered, pompom and collar varieties of dahlias, as a rule, do not form.
Blooming dahlia. To achieve not early, but more lush flowering of the dahlia, the first bud is removed. This technique preserves the strength of the bush for development, increased growth of lateral shoots and, therefore, more abundant flowering. From mid-June, one should not forget to regularly remove faded inflorescences, so you can prolong flowering and preserve the decorative effect of the bush.
On tall and large-flowered dahlias, you can leave 1-2 flowers on the shoot, removing the rest, then the inflorescences will be larger.
Reproduction. There are three ways of propagation of dahlias: seed, dividing tubers and cuttings.
Since seeds collected from plants from free pollination do not convey the characteristics of the variety, dahlias are propagated by seed, which are grown as an annual crop: dwarf non-double and semi-double varieties. Seedlings grown from seeds are hardened in greenhouses and planted after spring frosts.
The fastest way to reproduce is by cuttings. In February, dahlia tubers are taken and germinated until the sprouts grow 8-10 cm. The sprouts are cut off, treated with a growth stimulator solution (root, heteroauxin) and planted in wet sand. The rooting room temperature should be in the range of 22-24 ° C, humidity 70-80%. To maintain air humidity, cuttings must be sprayed periodically. After a week, the rooted cuttings are planted in pots with a diameter of 8-10 cm with light nutritious soil. After disembarkation, they need to be shaded for 2-3 days. When young plants reach a height of 20-30 cm, have a developed root system and a few bright green leaves, they will be ready for planting in open ground. By this time, the soil should already warm up well.
And finally, the simplest and most common way of dahlia breeding is by dividing the tubers.
Important: dahlia root tubers, which are more than 3 years old, need to be divided. If such old tubers are not separated, they will become massive, with a large green mass during the growing season. Plants from such root tubers become vulnerable to fungal diseases, and the inflorescences become small.
Tubers are taken out of storage in mid-April and dry and rotten parts are removed with a sharp knife, the cut points are sprinkled with crushed coal or foundation. For germination, they are placed in a bright, warm place (18-20 ° C), on a small layer of soil and sprinkled with a layer of loose substrate (peat or moss). After 10-14 days, when the buds began to germinate, the tubers are carefully separated into several parts. Dense tubers are cut into several parts with a sharp knife so that each part contains 1-2 buds with a part of the root collar and 2-3 tubers. After the slices have dried a little, the tubers are planted in open ground.
Diseases and pests. The most common pests of dahlias are aphids and spider mites, slugs and viral mosaics. Plants affected by aphids and mites should be regularly treated with insecticides. Against slugs, you can try to treat the bushes with decoctions of wormwood and celandine. Carry out processing once a week. Dahlias with viral mosaics need to be dug up and removed.
Plants in winter. If dahlias are not grown as an annual crop, then they must be placed in a cool room for the winter.
In October (after the first frost), when the stems of the bushes begin to turn black, the stems are cut off or broken off at a height of 10-20 cm from the root collar. The bushes are carefully dug in a circle, removed from the ground and just as carefully cleaned the tubers from the soil. Then the tubers are washed under water and dried in the sun for 4-6 hours or 2-3 days indoors (no more). After drying, you need to cut off the stems, leaving hemp no more than 1-2 cm, otherwise there is a risk of rotting tubers. Next, the tubers are placed in bags with sawdust or peat and a place for winter storage is selected.
It is ideal to store dahlia tubers in a frost-free room with good ventilation, an air temperature of +3 + 7 ° C and a humidity of 60-70%.
Important: the tubers must be checked at least once every 2 months, making sure that they do not rot and dry out. Rotten parts must be removed, sprinkle with charcoal.
In apartment conditions, tubers can be taken out on a glazed balcony, in extreme cases - stored near the balcony door. If possible, place them in the basement, but do not forget to check them from time to time.