The plants parts that need to be collected for propagation
depend on the method of propagation that will be used.
The basic types of propagation are:
Cuttings
Cuttings involve removing a piece from the parent plant and that piece then
regrows the lost parts or tissues.
Both woody and herbaceous plants are vegetatively propagated by cuttings of stems,
leaves and roots.
New plants can be grown from parts of plants because each living plant cell
contains the ability to duplicate all plant parts and functions.
Mature cells can change into MERISTEMATIC (mare-ah-ste-MAT-ick) cells that are
found at rapid growth sites like buds.
Softwood cuttings are pieces of new growth taken from woody stock plants.
These cuttings must be taken before the new growth starts to harden.
Hardwood cuttings are taken from tissue which has become woody.
Other forms of cuttings are leaf cuttings and root cuttings.
Layering
Stems that are still attached to their parent plant may form roots where they come in contact with
a rooting medium.
This method of vegetative propagation is generally successful, because water
stress is minimized and carbohydrate and mineral nutrient levels are high.
The development of roots
on a stem while the stem is still attached to the parent plant is called layering.
A layer is the
rooted stem following detachment (removal) from the parent plant.
Division
Strictly speaking, division is the cutting or breaking up of a crown or clump of
suckers into segments.
Each segment must have a bud and some roots.
These segments are replanted and grow into new plants identical to the parent.
Most garden perennials should be lifted and divided when they become overgrown and begin to lose vigor.
Vigorous growth in most perennials occurs on the outer segments of the clump.
Old growth in the center of the clump is discarded.
- BULBS AND CORMS
- Bulbs can be propagated by removing small bulblets or offsets that form at the base of the parent bulb.
These small bulbs take 2 or 3 years to mature into plants that flower.
Place offsets in rich, light soil for their development.
This same procedure should be followed for plants which form from corms, such as gladiolus.
- TUBERS AND RHIZOMES
- Tuberous plants can be dug up and the TUBERS separated.
In separating the tubers, each must have a segment of the crown that contains at least one eye or bud.
Rhizomes grow and develop buds along their length.
The rhizomes can be dug and cut into sections that each contain at least one eye or bud.
Seed
Description of Seed:
A seed is composed of three basic parts: the embryo, food storage tissue and
the seed covering. The embryo is a new plant resulting from union of male and
female gamete during fertilization. Cotyledons, or seed leaves, are attached
to the embryo. Seeds are classified by the number of cotyledons attached.
Monocotyledons (monocots) such as grasses and palms have one cotyledon,
while dicotyledons (dicots) such as bean and peach have two. Plants such
as pines are gymnosperms and their seeds may
contain as many as 15 cotyledons.
A mature viable seed contains enough stored food or energy source for seed
germination and early seedling growth. The cotyledons of dicots usually
contain this food reserve, while some seeds have a mass of food reserve
called endosperm surrounding or in contact with the embryo (e.g., corn).
Seed coverings can consist of the seed coat and parts of the fruit or seed pod.
These structures protect the embryo and food reserve inside the seed.
They can also inhibit germination until conditions are suitable for germination
and seedling development. A single orchid seed pod may contain over 3 million
seeds but 500,000 to 1 million seeds per pod is common in many plant species.
Every genus and species of plants with seed that is collectible is different
and each varies through the season with the environment.
Collecting seeds of
plants that are easily propagated by seed are the best to start with.
Collecting seeds of plants that propagate more readily by division or other
means is impractical unless you have a large area to cover and
you can direct sow the seed.
Plants that grow best from seed include those with long taproots, and other plants that do not easily transplant.
Bear in mind when you transplant something you have taken it from the habitat
from which it has already adapted and will usually have a much greater rate
of failure than starting from seed, which will allow the plants to adapt to
their "new" environment more readily.
Collecting the seed of biennials is also significant because there is the
potential of having yearly bloom by seeding every year.
Seed propagation offers genetic variability; thus, the offspring may not have
the exact characteristics of the parent plant. While genetic variability is a
disadvantage if the goal is to grow a uniform crop it is the most desirable
method of restoring native specess to natural habitats. Seedling variation
will be quite high in some plants, while other plants will retain more
characteristics of the parent plant.
Don't forget that seeds are living organisms and must be handled accordingly
if propagation is to be successful.
The optimal method of propagation depends on the species, the available sources
and the facilities to be used for propagation.
If you plan to perform the propagation yourself, we recommend that you
complete the next module,
Propagation of Native Plants,
before implementing
your collection project.
If you plan to use the services of a contractor orcommerical nursery for
the propagation step, they will provide advice on collection, and it is best
to coordinate with them before implementing your collection project.
Exercises
- Choose one or more species and discuss the possible and preferrable propagation options.
Suggestion: native grasses and trees are good choices for discussion.
- Visit or call a local nursery that provides native plant propagation services
for information about their capabilities and recommendations regarding collection.
References
- Basic
-
Asexual Propagation of Plants, Ohio State University Master Gardener Training Manual
-
http://www.hcs.ohio-state.edu/mg/manual/prop2.htm
-
Sexual Propagation of Plants, Ohio State University Master Gardener Training Manual
-
http://www.hcs.ohio-state.edu/mg/manual/prop.htm
- Advanced
-
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The content of the page was last modified
2008-05-06