A fascinating facet of gardening is the science of plant propagation.
Gardeners consciously or unconsciously use one or more propagation methods in producing their garden plants.
The simple act of raising plants from seeds is one important method.
“Slipping” a geranium, planting a gladiolus corm, or transplanting young strawberry runner plants are other recognized methods of vegetative propagation.
Why So Many Different Methods?
Gardeners have learned through experience that one method of propagation works best with one plant species, another method works best with another, and so on.
Often, several methods can be used with a particular species: The best way, therefore, depends on the kind of plant, the season of the year, the facilities available, and so on.
For example, if one wishes to reproduce the McIntosh apple, the propagator can start it from hardwood cuttings, bench grafting, budding, or even air-layering.
He would use a grafting or budding method to produce many new plants.
If he has more time in winter, he will bench-graft, or if he has more time in summer, he may use one of several budding methods.
If interested in only a small number of plants, he might use an air layering method.
If he were to grow seeds from a McIntosh apple, he would find they would not come true to variety, and it would take several years longer for trees to reach fruiting age compared with grafted plants.
Vegetative Propagation
Most herbaceous perennials, ornamental trees, shrubs, and small fruits are propagated by vegetative means.
This is especially true where wide horticultural varieties (or clones) exist, as in the following:
- Dahlia
- Lily
- Gladiolus
- Apples
- Plums
- Lilacs
- Flowering crab apples
Vegetative propagation can be grouped into five categories.
These are:
- Cuttings
- Layering
- Grafting and budding
- Division and separation
- Use of specialized organs and structures (bulbs, corms, rhizomes, tubers, runners, rootstocks, and others)
Cuttings
Of the various methods, cuttings are the most widely used. Both herbaceous and woody plants lend themselves to this method.
Herbaceous plants, like chrysanthemums, African violets, coleus, and geraniums, are propagated from the stem or upper parts of the plant.
Root pieces are employed in a few plants, such as Oriental poppy, phlox, and horse-radish.
Usually, the end tip of the plant gives the best source of cutting material, although other parts may be satisfactory. These are known as softwood cuttings.
Many plants will reproduce from leaves or parts of leaves. These include numerous succulents, African violets, gloxinias, and begonias. These are called leaf, leaf buds, or mallet cuttings.
If young stem tips are taken from woody plants during the growing season before the tissue becomes hard, these are called greenwood cuttings.
Hardwood cuttings are taken in fall or winter after deciduous plants are dormant.
Poplars, willows, dogwoods, and other woody plants are frequently handled this way.
Division And Separation Propagation
Propagation by division and separation or by using various specialized storage structures of plants are methods used to increase many important plants, including:
- Dahlias
- Gladiolus
- Tulips
- Daffodils
- Iris
- Certain grasses
Gardeners who want to delve further into propagation will find Montague Free’s book “Plant Propagation in Pictures” very helpful.
Experiment stations and extension services of colleges and universities throughout the country have excellent bulletins available on this subject.
44659 by Leonard A. Yager