Successfully Propagating Orchids
Successfully Propagating Orchids
The simplest method is vegetative propagation using parts of a growing plant. With this method, the offspring will be exact replicas of the parent plant. A much more complicated method is generative propagation, from seed, which goes hand in hand with the exciting possibility of raising a new cultivar. Just what the new young plants will look like is always a great surprise. Even beginners have managed to achieve some astonishing success using this method.
This method of propagation involves taking rooted or unrooted, large or tiny parts of plants from a parent plant and then continuing to grow these parts in pots or test tubes. No pollination will influence the genetic material and thus the new plants will be exact replicas of the parent plant. Orchids can be vegetatively propagated in many different ways:
- by division
- by cutting off small daughter plants; shoots or bulbs
- by rooting shoots or
- through meristem culture. This involves peeling a microscopically small part of a cell from a budding shoot and placing it in a test tube filled with a sterile nutrient solution. By constantly turning the test tube, a lump of tissue is formed that can be divided up into as many pieces as desired and cultivated further in another test tube with more nutrient solution. In this way, hundreds of identical plants (or clones) can be create from one original plant. This method cannot be used at home as it involves technical equipment only found in laboratories. I can, however, recommend the purchase of orchids propagated in this manner — called mericlone orchids. They are known to be highly resistant to disease (particularly to bacteria and viruses).
Very young or recently purchased flowering orchids are not suitable for vegetative propagation. However, you can go ahead with propagation from:
- plants that are several years old, large, completely healthy and strong
- orchids which are reluctant to flower and are quite old (often found in hybrids from several different genera, for example Brassolaeliocattleya.
- daughter plants which have formed by themselves on the parent plant and have produced rootlets
- plants with overhanging bulbs that are on the point of dropping off
- orchids which automatically split into two or more pieces while you are repotting.
The right time of year to propagate orchids
Orchids cannot be propagated at just any time. The best time is in the spring, during repotting or after flowering as the parts of the young plants will root better if they are able to grow on through the warm months with more light.
The importance of good hygiene
Any type of propagation is stressful for an orchid. During and after propagation, however, it is more vulnerable than at any other time to attack by disease-causing agents. Good hygiene is the best preventive measure.
- Before and after cutting, disinfect your scissors or knife with pure alcohol.
- Dust all cut surfaces or injured parts with antiseptic charcoal powder.
- Large cut surfaces may be treated prophylactically with a fungicide.
- Always allow cut surfaces to dry a little before planting the cutting in fresh .
Methods of vegetative propagation
The manner of propagation will depend on growth. Monopodial orchids with only one shoot should be propagated in a different manner fromwith several shoots. There are various different methods, some trickier than others.
Propagation through division
Monopodial (one shoot) orchids often fall apart into two or more plants when the old compost is shaken out during repotting. You can then repot each plant individually.
Sympodial (several shoots) orchids are divided so that each new plant possesses at least three to five bulbs with leaves. The resulting pieces will only regenerate if they have these leaves; the bulbs only if they are fat and green.
Propagation from the division of monopodial orchids
Example:If you remove the compost during the repotting of lady’s slipper orchids, you will find that the rootstock automatically falls apart.
Never divide plants that do not have at least six strong, healthy shoots. Be careful when dividing. Torn sections will either not grow well or will not grow at all.
Propagation from the division of sympodial orchids
You should only divide this plant if the part to be removed has at least three bulbs with leaves. For example, six single-row bulbs can be divided into two plants. In, however, leafless, plump bulbs can also be divided up.
Propagation from daughter plants
Remove the daughter plants that have formed on the stalks of flowers – some growers maintain that these are formed through mistakes in care. As soon as they have formed their own rootlets, cut them off, together with a small portion of the stalk of the parent plant, and then fix the daughter plant to the surface of the compost with a wire clip.
A special growing paste can be obtained in the gardening trade which stimulates the formation and growth of daughter plants on flower stalks. The paste is applied to an “eye” on the stalk and the hormones contained in the paste trigger the formation of a daughter plant.
Propagation from the cuttings of monopodial orchids
Cuttings for propagation can be taken from orchids that have grown too tall. To do this, cut off the uppermost part of the stem exactly beneath the aerial roots. Place the removed part of the plant in a very aerated, coarse bark compost.
The parent plant must be at least 20 cm (8 in) tall if it is to recover from the procedure.
Vanda andmay be propagated from daughter plants that grow on the end of an old flower stalk. Cut off the daughter plant about 2 cm (1/4in) below its aerial roots and place it in compost that is heat- and air-permeable.
The aerial roots must not be too short.
Monopodially growing species, like Aerides, Angraecum, Renanthera and Vanda, may be divided if they are older and healthy and have plenty of leaves and lots of aerial roots. Take the cutting at a level of about 20 cm (8 in), close beneath the aerial roots, and place the cut-off portion in a small pot. This cutting should form shoots after a few months. This is more difficult with Phalaenopsis!.
Propagation from cuttings of sympodial orchids
You can take cuttings from the stalks of this genus of orchids. Each cutting should be about 10-15 cm (4-6 in) long and possess four or five segments. The pieces should be placed longways in sphagnum moss mixed with polystyrene flakes, and kept moist and warm.
Read more on propagating orchids and potting orchids …