Blehnum, or Derbyanka - capricious fern
Blehnumy, or Derbyanki - ferns in the culture are rather capricious. It is best to grow blehnums on a "tropical window." The leaves are a bit like a “hat” of palm leaves. In older specimens, the trunk is clearly visible at the base. Read about the features of growing this fern in our article.
- Derbyanka - Botanical Description
- Types of Blackheads
- Requirements for the cultivation of blehnum
- Propagation of blackheads
- Diseases of derbyanki, or blehnumov
Derbyanka - Botanical Description
Rod Derbyanka, or Blehnum (Blechnum) includes about 140 species of ferns of the Derbyankov family (Blechnaceae), distributed mostly in tropical and subtropical regions. Under natural conditions in Russia, one species of derbyanki grows - the spiny derbyanka, or the Blehnum spiny (Blechnum spicant).
In nature, derbyanka is a large, palm-like plant with branches reaching 1 m in length. The stalk of the fern is a modified rhizome, in old plants in indoor conditions reaches a height of about 50 cm, is covered with brown scales. Its branches are once cirrus-dissected, about 50-60 cm long, light green in color. Sporangia on the underside of the leaf, closer to the edge of the segments.
Types of Blackheads
In indoor conditions, the following types of derbyanka are most often grown:
- Blechnum humpback, or Derbyanka humpbacked (Blechnum gibbum) It has bright green leaves with almost no petioles. The most popular species in indoor floriculture.
- Brazilian Blechnum, or Derbyanka Brazilian (Blechnum brasilense) It has broad olive green leaves.
- Blehnum Moore, or Derbyanka Moore (Blechnum moorei) A small bush about 30 cm in size, petioles of leaves almost black in color, while the leaves themselves are dark green and shiny.
- Blechnum serratus, or Derbyanka serrate (Blechnum serrulatum), a synonym is Blehnum Indian, Derbyanka Indian (Blechnum indicum).
Requirements for the cultivation of blehnum
Lighting: the place must be shaded from direct sunlight - i.e. diffused light or light partial shade. Blehnum is a shade-tolerant plant, it is recommended to place it on the north or west windows, as well as in the back of the room. Direct sunlight can harm the plant.
Watering: Only with warm, settled water containing no lime. Watering in spring and summer is plentiful, in winter it is moderate, but the soil should be moist all the time. Drying as well as excessive moisture in the soil are equally harmful to the blehnum. It is advisable not to water the young plant from above, but to lower it into the water with the pot, leaving for 1-2 minutes. After this, excess water must be allowed to drain.
Air humidity: Like many ferns, Blehnum likes moist air, but spraying can spoil the leaves. Therefore, pots with plants are placed on trays with wet expanded clay. The batteries are hung with a damp cloth in the winter.
Transfer: transplant is carried out in spring, when the roots fill the entire pot. The soil should have a slightly acidic reaction. Blechnum is planted in a soil substrate suitable for most ferns. As a rule, it consists of 2 parts of peat land, 2 parts of humus, 1 part of chopped moss and 1 part of sand. The plant is transplanted as it grows, when it becomes crowded in a pot. Two days before transplanting, the fern should be watered.
Top dressing: in the summer, liquid fertilizer for indoor deciduous plants every two weeks. Blehnum is very sensitive to excess fertilizer, so the dose should be taken 2 times less than recommended by the manufacturer. Winter-fall - without top dressing.
Pruning: does not need.
Temperature: the most optimal for growing ferns - 18-22 ° C. High temperatures can cause the plant to get thermal burns. Blechnum needs to be protected from drafts.
Propagation of blackheads
Derbyki is propagated by spores and division of rhizomes. When transplanting, the rhizomes are divided into parts with a sharp knife, the places of the slices are sprinkled with crushed charcoal, each part is planted in a separate pot. Pay attention to the number of growth points. If there is one growth point or they are few in number, then you can’t divide the plant, this can lead to death. Young plants after division do not immediately start to grow.
You can try to propagate the plant from the spores formed on the lower surface of the leaves. They are sown in early spring, best of all in a nursery heated from below, where a temperature of 21 ° C is maintained. Cut a leaf of the plant and scrape off the spores on paper. Pour in a nursery a layer of drainage and disinfected soil for sowing seeds. Water the soil well and disperse the spores as evenly as possible. Cover the nursery with glass and place in a dark, warm place.
Every day, briefly remove the glass for ventilation, but do not let the earth dry. The nursery should be kept in the dark until the plants appear (this will happen after 4-12 weeks). Then transfer it to a bright place and remove the glass. When the plants grow, thin them, leaving the strongest at a distance of 2.5 cm from one another. Young specimens well developing after thinning can be transplanted into pots with peaty soil - 2-3 plants each.
Diseases of derbyanki, or blehnumov
Leaves turn yellow, brown spots appear on them - means the room temperature is too high (above 25 ° C), which is not desirable for ferns. The cause may also be irregular or insufficient watering and frequent spraying.
Leaves turn yellow, the plant grows poorly - Too low humidity in the room, the proximity of the heating system, similar symptoms can be observed if the plant is planted in very heavy soil or too spacious a pot.
Leaves faded, translucent, lethargic - Too intense sunlight.
The leaves are pale or dull, the ends turn yellow or brown, the plant does not grow or grows poorly - lack of nutrition, too small or too large pot.
Leaves can turn yellow, brown, curl and fall, young leaves wither and die - at too low a temperature in the room, from exposure to cold draft, irrigation with cold water, when irrigating with hard or chlorinated water.
No one says that ferns are easy to grow, but this is all the interest, the main thing is that it works. Although capricious, the result is worth it!