How to Propagate Plants Simply
INTRODUCTION
This topic is so vast and techniques are so planted specific, it will be impossible to even cover the tip of the iceberg on this page. However, we hope to provide you with some useful information to introduce you to the many ways that you as a home gardener can reproduce plants for yourself and also become better aware of the many techniques that are used in the nursery trade to propagate plants for your use and enjoyment.
A lot of extra reading on this subject is necessary to fully understand all the complexities and aspects of plant propagation. We will only cover some simple methods that practice that the amateur can use, just as we do every year to enhance our landscape and plant collection. Please feel free to contact us is you have further questions on this topic and we will try to help you further.
PLANT PROPAGATION METHODS
Sexual Propagation: This term refers to the reproduction of new plants from viable seeds or spores produced by the plants natural reproductive system. This method is used mostly for annual and perennial plants which don’t require long growth periods, plants that cannot be reproduced by other means, or for plants that are reproduced through hybridization. This page will not cover sexual propagation.
Asexual Propagation: This term refers to the reproduction of new plants from means other than seed. These methods produce genetically identical plants or clones. Methods of asexual propagation include the following:
Commonly Used Methods: (Can by done by the amateur gardener)
Stem Cuttings (Hardwood, semi-hardwood, or herbaceous) Leaf Cuttings vein, petiole, or leaf section) Division (bulbs, corms, tubers, roots and stems, rhizomes, pseudobulbs, etc.) Layering (air and ground) Root Cuttings Leaf Bud Cuttings Cane Sections
Specialized Methods (used mostly in commercial nursery trade):
Grafting and Budding: (there are many techniques used for grafting, depending on the plant); Tissue Culture (this technique is used commercially and will not be covered)
PROPAGATING NEW PLANTS
Important considerations in successfully propagating new plants include the media, rooting hormones, misting or continuous moisture, light and temperature. All these factors determine success or failure in asexual plant propagation.
By far, the most common and amateur-friendly methods of plant propagation are tip/stem cuttings and simple division. These techniques apply to the vast majority of plants grown for landscaping or personal enjoyment. I will discuss the basics of these techniques.
Propagation by cuttings:
Stem tip cuttings: This involves the following steps:
- Cut a terminal section from an un-branched stem of approximately 6 inches length just below the leaf axil. (length varies with plant size).
- Remove the lower 2/3rds of the leaves and any flower buds Dip the base in a rooting hormone such as Roottone or Hormodin placing the lower 1/3rd of the cutting into a rooting medium (coarse sand, perlite, or very porous peat and sand mixture)
- Keep the cuttings moist at all times via a sprinkling system or enclosed to maintain a constant moisture level.
- Periodic aeration is necessary as well. Keep cutting out of direct sunlight or any condition that would produce stress.
- If under the misting system, more light can be tolerated. Check cuttings periodically and carefully to determine the extent of rooting.
- Remove cuttings only when fibrous feeder roots are evident Pot cuttings in a loose but organic potting soil and continue to stimulate root development with a root stimulating fertilizer until pot bound.
- Keep well watered and reduce stress during this period (e.g. place in shaded area)
Please note that the steps above are representative and generic in nature. The type of plant, the length of time needed to root, the strength of the hormone needed, and the proper time of year to take cuttings are very plant-specific. As a general rule, herbaceous plants root quickly and easily whereas woody plants take much longer and require stronger levels of rooting hormone.
The time of year is much more critical for propagating woody plants. Refer to reference books or talk with people who have had experience with propagating certain plants for more specific advice. Plants are best rooted in either herbaceous, semi-hardwood, or hardwood conditions depending on the specific plant.
Gardening TIP: HOW TO SET UP A SIMPLE, INEXPENSIVE PROPAGATION SYSTEM
Get a 10 or 20 gal. used aquarium from a garage sale or other source, and a piece of glass or clear plastic large enough to cover the top. Place 6″ of coarse sterile sand in it Keep the sand moist, but not drenched. If excess water builds up at the bottom, use a basting syringe to suction out water.
I prefer to use a talc-based powder such as Hormodin, Roottone, etc, For semi-hardwood cuttings, a .3% strength of active ingredient is necessary (e.g Hormodin #2). For hard to root cuttings, use a .8% (e,g, Hormodin #3). Packets of rooting hormone found in most garden centres are only .1% used for soft stem or herbaceous cuttings and house plants. You can also set up an outdoor sprinkler system using a timer connected to a hose bib – available at most hardware stores, but this restricts you to only summer propagation.
Plant Division:
This technique is simple and used most frequently with mounding, clumping, or suckering plants such as most perennials, ornamental grasses, and many tropicals. A hardwood, plant can be divided this way if multi-trunk and each trunk have produced its own roots. All that is involved is a slice with a sharp knife through the base to divide the plant into smaller bases each with its own set of established roots.
Suckering and stoloniferous plants produce new plants from underground roots and offshoots at the base. These new plants can be easily divided by severing them from the mother plant and reestablishing them on their own. A root promoting fertilizer always helps the re-establishment process.