The Craft of Asexual or Vegetative Propagation
By the Fearless Gardener
Asexual or vegetative propagation of plants by cuttings is a very important part of horticulture. Asexual techniques allow the increase of plants so that all the children are genetically identical to the parents. This differs greatly for sexual propagation where there remains the potential for diverse genetic variation. Seedling populations from many horticultural crops are so variable that asexual propagation affords the only way to practically maintain these individuals in order to retain there uniformity.
Buying rooted cuttings may save time and energy at some point you still can occasionally to supplement your growing operation or bring in new varieties. But buy learning the craft of propagation you will have control of your stock and not be missing out on the excitement of what high performance gardening is all about.
There are many ways to propagate plants using cuttings. The process involves determining which cutting type is best suited to you. Cuttings can be made form all vegetative portions of the plant including simple modified stems, bulbs, tubers, leaves, and root tissues.
Stem Cuttings:
These are the most used types of cutting. In general, they can be divided into four groups: the hardwood, softwood or herbaceous, and the cane cutting. When preparing a stem cutting, a section of stem tissue with lateral or terminal buds is obtained. Typically, stem cuttings are made from terminal ends shoots, generally three to five inches long, and are removed from the parent plant at a point just below a healthy leaf. Except for hardwood and cane cuttings, the stem cutting should have three to four leaves for the quickest rooting. The leaves from the basal 1/3 of the stem cutting should be removed.
Semi-hardwood cuttings:
These types of cuttings should be taken in mid summer from matured wood for best results.
- Use terminal or lateral branches.
- Determine cutting length and trim cutting.
- Remove leaves from the basal
- Apply rooting gel (many to choose from).
- Plant in media and firm.
- Put under mist.
Herbaceous or Softwood stem cuttings:
These are prepared from soft, succulent, herbaceous growth of an extremely wide range of horticultural plant e.g., mums, hydrangea, fuchsia, privet, pyracantha, lilac, forsythia, magnolia, weigela, cotoneaster, dogwood, etc…. If the leaves of cuttings are large, they may be cut in half in order to reduce water loss.
- Follow procedures for semi-hardwood cuttings: remove cuttings, determine length and trim.
- Strip lower leaves.
- Apply rooting gel.
- Pre-dibble hole in media, plant, firm media around base of cutting.
Cane Cutting:
These are used to propagate dumbcane, Chinese evergreen, dracaena, and similar plant which produce long cane-like stems. The cane which remains after a tip or stem cutting is removed for the parent plant can be cut off three inches above the soil line. This portion of stem or cane is then cut into small sections two to three inches long so that each piece has at least two leaf scars and a dormant bud.
- Remove portion of stem.
- Leave at least two nodes and a dormant bud.
- Place stem on its side with dormant bud facing upward, bury stem into media 1/2 of stem diameter.
- Place under mist.
Leaf Cuttings:
In most of these cuttings, adventitious shoots form along wound surfaced near vascular tissues.
- Whole leaf (African Violet, Peperomia).
- Remove leaf on media surface with petiole inserted into the medium.
Leaf Piece (SANSEVIERIA)
- Remove section of leaf.
- Cut into pieces and plant in media maintaining polarity.
Leaf Piece (Begonia)
- Remove a leaf from the plant leaving approximately 1/4 -1/2 inch of petiole.
- Divide leaf into triangular sections being sure to leave a portion of the petiole with each leaf piece.
- Place petiole portion in media.
- Firm around cutting.
Leaf Bud Cutting:
As the name implies, it consists of a single leaf attached to a piece of stem tissue (1- 1 1/2 inches long). A dormant bud is located in the axil of the leaf and will give rise to the new shoot.
- Remove section of stem.
- Cut stem into sections, each with a leaf attached.
- Place horizontally in media, with leaf exposed.
Root Cuttings:
These are applicable for the propagation of more woody plants commonly realized. They are also beneficial as a means of propagation fruit root stocks. Root cuttings are usually obtained during the dormant season from found stock plants when roots are well supplied with carbohydrates.
- Remove sections of roots from plant.
- Thick root (pencil size) should be cut into three to four inch sections.
- Plant maintaining polarity (either in vertical position or horizontal position) completely covered media.
- Thin roots should be cut into three to four inches sections and place horizontally on the surface of media and covered lightly.
- Place under mist.
Helpful Hints To Ensure Rapid Rooting Of Your Cuttings
- It’s good to use a dome to maintain high air humidity around the plants while developing roots and be sure to slightly vent.
- The use of a high quality heating mat under the plants can considerably speed up the rooting process especially in cool areas.
- A professional high quality rooting gel that can promote a sterile rooting environment and ensure fast rooting of cuttings will increase your percentage.
- An automated sub-irrigation propagating system makes it easy to initiate the rooting of large numbers of cuttings with consistent results.
- Plant non-succulent cuttings as soon as possible after severing for the parent plant and make sure that the growing medium is in close contact with the inserted part of the plant.
- Don’t keep tugging at the plants to see if they have started rooting – new growth is the best guide.
- Pure high quality nutrients rich in phosphorus along with vitamin b-1 will rapidly promote a strong and healthy root system for your plants.