How to Propagate Your Plants
Certain varieties of perennials can be used to create new plants.
This is accomplished by the use of various propagation methods.
The general methods used include cuttings, division of old clumps,
propagation from leaves, and budding. Some varieties can be propagated
by a number of methods; for others, only one way works.
Cuttings
Cutting is the process of removing a small portion of a growing
plant and treating it so that roots are developed. The cutting
can then be transplanted and will, in time, produce its own blooms.
Cuttings are usually made from a portion of the stem, from leaves,
from tubers or from roots.
Cuttings are usually rooted in a mixture of sand and peat moss.
Some varieties can be induced to root in water, in sphagnum moss,
or in light, sandy soil. For softwood cuttings, made from the
wood stem of soft-stemmed plants, insert small pieces of stem
about 2 or 3 inches long in 4-inch-deep (or deeper) flowerpots,
with about one-half their length exposed.
Some provision should be made for shading. The flowerpot should
be inserted in another pot filled with water, so that there is
a steady seepage through the porous clay. The hole at the bottom
of the pot should be tightly plugged with a cork
Practically all perennials can be propagated by cuttings. The
clipping itself should be made at a sharp short diagonal, just
below a node or joint. The cutting should be wrapped in damp newspaper
and exposed to the air for a half-hour or more. This does not
apply to plants which exude a milky juice. Such cuttings should
be sprinkled with water and exposed to the air for two hours.
Many perennials can be propagated by causing a leaf to root.
Plants with thick fleshy leaves, like begonias and gloxinia, are
particularly suited to this method of increasing their number.
The leaf stem is inserted in the rooting medium and cared for
as in the case of cuttings. Some plants can be propagated by placing
the leaf flat on the rooting medium and weighting it down with
pebbles. A slight cut is made through the main vein of the leaf.
The use of plant hormone will materially improve the chances
of propagating successfully from leaves, even in the case of plants
generally considered difficult to propagate by this method. Hormones
are particularly successful with holly, magnolia, rhododendron,
azalea, taxus and many others.
Division
Dividing clumps is one of the simplest methods of propagation.
It is, in addition, good for the old divided plants. Many perennials
deteriorate if left in clumps for too long a period. Dividing
them insures continuous health and growth. The plants are carefully
removed from the soil, in clumps, and divided simply by pulling
them apart. Care should be taken to injure the roots as little
as possible. Divided plants are potted, or if the division is
done early in spring, as with the hardier perennials, the new
clump is planted in another section of the garden. The new planting
should be well fertilized and watered.
Layering
Layering is another simple method of propagation. It is adaptable
only to those plants which root easily when their stems are in
contact with the ground. Broad-leaved evergreens in particular
(i.e., rhododendron) lend themselves well to this method.
Simple layering involves anchoring the supple
stems of plants into the adjacent soil by bending them over and
burying them. Black raspberries, for example, are easily propagated
in this way. For plants with less supple stems, a notch is cut
about 18 inches from the tip of the stem and propped open with
a twig or sliver of wood. The branch is then bent to the ground,
and the notched portion covered with soil. This type of layering
is best done in spring or summer. Leaves should be removed from
the stem which is being used for propagating.
Serpentine layering is used for plants with long
supple stems (vines, for instance) which travel close to the ground.
A number of plants may be obtained from one stem by covering it
with earth at different points; the tip should always be left
exposed, however.
Air Layering
Air layering is a very modern and popular method, adaptable
to trees and woody plants. A portion of a straight branch or stem
is cleared of bark down to the wood, and surrounded with moist
sphagnum moss. The moss should be kept damp. Some manufacturers
provide plant food and hormone which can be rubbed into the cut,
and a plastic wrap for the moss which is also impregnated with
plant food. After the notch or stripped area has rooted well,
the branch is cut off and replanted.