Orchids are considered elegant, graceful plants. And the Dendrobium orchids are in no way inferior to this impression. With their full flowers, which grow column-like along the plant, they look luxurious. The plant has aerial roots, is not very demanding and still flowers reliably in most cases, sometimes even two to three times a year with good care. There are now many different hybrid species and many colors. The classic orchid colors are white and violet, but they also come in yellowish and reddish tones. Individual cultivars have bicolored flowers, which are a different color at the edge of the flower than in the center of the flower. Orchids are perennial and can be propagated in the home environment. The flowering period can even be artificially extended by a cool location after the first flower has opened. As a result, the magnificent flowers are a feast for the eyes even longer.
Table of Contents
sowing
Sowing by seeds is not practiced, propagation by plant division can be attempted at home.
plant
The plants have opposite leaves and produce flowers along the length of the plant, giving the appearance of a flowering column. In addition, the plant has bulbs, also called pseudobulbs, which serve as storage for water and nutrients. The bulbs of the Dendrobium orchids consist of several, approximately uniformly thickened internodes. Due to their natural habitat, they form long aerial roots and mostly grow on trees (epiphytic), lithphytic, i.e. on rocks or on the ground (terrestrial).
repot
Orchids grow best in small pots. Therefore, the plant should only be repotted if the shoot really has no more space or if there are visible defects on the pot surface. If the substrate appears calcified, greasy, covered with moss or algae, it is time to repot. The same applies as soon as plant parts begin to rot or decompose.
Spring is the best time to repot orchids. Then the flowering period is usually over and new shoots begin to grow. Here are the most important steps:
- Carefully remove the plant from the pot
- Remove old substrate
- Cut off rotten, dried up, damaged roots, flowers, leaves and buds
- Use a sharp knife to avoid crushing the plant parts
- Choose a pot size with space for at least two shoots
- Caution: pots that are too large lead to excessive moisture and can cause rot
- insert plant
- Place the oldest shoot at the edge of the pot
- Carefully screw in the roots and place in the pot
- Fill in the substrate
- Shake the pot and, if necessary, knock it against the edge of the table so that the substrate is evenly distributed
- Cover plant shoots to the base
- press on the substrate
- Water, before watering again, the substrate should dry out completely
maintenance
The commercially available Dendrobium orchids and their hybrids are relatively easy to care for. There is a greater tolerance of water and temperature in which they can thrive. In principle, the orchid requires a higher humidity, so it is advisable to mist the plant regularly with a spray bottle.
In the resting phase of the Dendrobium nobilis, i.e. after the flowering period, it is possible that all the leaves will fall off. In this case, the plant should be moved to a cooler location and watered less until the new shoot has roughly reached the length of the old shoot. This procedure promotes flowering. The old bud should not be pruned for the time being either, since it can flower again after the rest period.
location and substrate
The optimal conditions for a vigorous Dendrobium orchid at home:
- Light conditions: bright, indirect light
- north-east or west-facing windows ideal
- direct sunlight too intense!
- with south-facing windows, darken the window during the sunny months (April – September) at midday
- Temperature conditions during the flowering period: Dendrobium nobilis rather cool to warm (16 – 22 degrees), other species up to 30 degrees possible
- after the Nobilis have bloomed, it is essential to take a cooler rest period (8 – 16 degrees), other species can be overwintered warmer
- cooler dormancy encourages flower growth
- if the Nobilis overwinters warmly, there are often no flowers in the following year
- artificial flowering time extension possible by colder place (around 16 degrees) after opening of the first flower
- use permeable orchid substrate! Never potting soil
- Choose substrate with lots of pine bark and coarser parts
- The pH of the substrate should be between 5.5 and 6.0
- the coarser the substrate, the easier maintenance will be
- coarse substrate absorbs moisture quickly, but releases excess water quickly
- Keep substrate rather dry
pour
The well drained substrate should not be damp. It is therefore essential to use a special orchid substrate that consists of structurally stable ingredients and quickly releases excess water. Pine bark is particularly suitable because it has a good shelf life and is low in nutrients. The substrate often contains carbonate of lime, perlite, chopped moss and radishes, which contain nutrients specially tailored to the orchid.
Since orchids usually grow epiphytically, they sit on trees and branches, their roots get a lot of water during heavy rainfall, but it also evaporates quickly in the air. However, humidity of over 50% is permanently present. The same claims apply to home care. The roots of the Dendrobium orchid are aerial roots and will rot if kept too moist. Therefore, using a spray bottle is suitable. It gently mists the plant with moisture but does not cause excessive moisture in the substrate. Alternatively, water can be added using the immersion method. The entire flower pot is immersed in a water bath for a few seconds and then set aside to dry. The plant only absorbs as much water as it needs.Overwatering can cause problems like yellow leaves and wilted bulbs.
The irrigation water should always be at room temperature and as soft as possible. Rainwater is ideal. If you live in a region with hard tap water, you can buy demineralized water at a hardware store to mix it with to reduce the salt content.
Fertilize
When fertilizing the Dendrobium orchid, less is more! Orchids can only absorb nutrients to a limited extent through their aerial roots and are quite sensitive to salt. During the flowering period, you can fertilize every 1 to 2 weeks with standard orchid fertilizer. Mineral fertilizers are easier to dose, whereas organic fertilizers usually release their effects more slowly over a longer period of time. Alternatively, you can use a regular flowering plant fertilizer at half the strength once a month during the sunny months.
During the rest period from September, fertilize the plant rarely or not at all. However, as the days get longer and bring more light, the plant’s metabolism increases. So you should start fertilizing again from February/March. A liquid fertilizer can be added to the irrigation water. It is sufficient to add this to every third watering.
It makes sense to adapt the fertilization to the light conditions, as the plant can absorb nutrients better on bright days. It is better not to fertilize on cool, cloudy and dark days.
In the best case, the water enriched with liquid fertilizer should be sprayed onto the aerial roots, leaves and the substrate using a spray bottle with a water atomizer. In the case of cold hibernation, no fertilizer is used at all. Monthly fertilization is sufficient during warm winter storage.
To cut
- use a sharp knife to avoid crushing the roots
- Cut off dried flower stalks
- leave at least three bulbs for a division cut or for rejuvenation, so that the plant will flower again soon
hibernate
The most commonly traded variety of Dendrobium orchid is the Dendrobium nobilis. In winter, after all the flowers and leaves have fallen off, it needs a cool resting phase in which important biological processes to maintain plant health can take place. The resting location should therefore be cooler than the summer location, and the plant can even stand in complete darkness. The addition of water should also be reduced during the winter period. Due to the risk of rotting, watering must be limited. It is advisable to only spray the upper parts of the plant and to keep the substrate relatively dry. If the Dendrobium nobilis overwinters too warmly, there are often no flowers in the next growing season. Fertilizing should be minimized during dormancy. Other varieties such as Dendrobium infundibulum, Dendrobium phalaenopsis or Dendrobium senile should be kept warm over the winter. However, the wintering site should be cooler than the summer site.
multiply
In the home environment, propagation can be undertaken by dividing the plant. Commercially, biochemical propagation is used because this is more promising. If the plant has enough offshoots (Kindl) and bulbs, it can be divided.
The kindl develop on older bulbs and should not be prematurely separated. For good growth of the kindl you can spray it daily with water and fertilizer. It is better to wait until the older bulb starts to dry up and turn yellow. Then the yellowish bulb can be cut off just below the offshoot (Kindl), if possible without damaging the roots of the offshoot. The offshoot obtained in this way with the part of the mother plant can then be planted in orchid substrate. For this, the substrate should be crushed to do justice to the small roots of the kindl.
Higher humidity improves growth. This can be achieved by covering with a hood or by a small indoor greenhouse. It is essential to avoid mold formation, so air the room several times a day.
sorts
Dendrobium nobilis is the most commonly found commercially. Occasionally there is also the Dendrobium infundibulum, Dendrobium phalaenopsis and Dendrobium senile to buy. In contrast to Dendrobium nobilis, these plants must be wintered warm because they do not like cold temperatures. They can also stand a little warmer in the summer months, but they also need a partially shaded place and do not like direct sunlight. However, they tolerate temperatures of up to 30 degrees.
diseases and pests
Most problems arise due to excessive watering. In such a case, plant parts can turn yellow, dry up or start to rot. Occasionally, the Dendrobium orchid is attacked by spider mites. The infestation is favored by a dry and warm environment. Fine cobwebs can then be seen on the leaf axils and leaf edges. Regular spraying of the plant prevents infestation with spider mites, as they find the humidity unpleasant. Spider mites multiply quite quickly in low humidity. An infested plant should be showered off first. To completely combat the infestation, you can cover the entire plant with a hood or plastic wrap to increase the humidity in a targeted manner. This coverage should be maintained for 3 to 4 days.
Conclusion
The Dendrobium orchid is an elegant plant that produces many beautiful flowers. The commercially available varieties such as Dendrobium nobilis are quite easy to care for. With the variety, however, the dormant phase, in which the plant should be overwintered in a cool place, must be observed. Other species such as Dendrobium infundibulum or Dendrobium phalaenopsis do not need a cold location during the rest period.
