Spring is that time of the year when plant enthusiasts develop the urge to propagate new plants. Plant propagation is an inexpensive way to fill your garden with the plants you love, by creating new plants from plants you already have. There are a myriad of ways to propagate plants. For both hobbyists and professionals, there is always a technique to explore. The more techniques you master, the better because not every technique works for every purpose.

The most common methods of plant propagation are through seeds (known as sexual propagation) and by using cuttings or divisions (known as asexual or vegetative propagation). Using seeds will cultivate more genetic diversity among your plants, whereas cuttings and divisions essentially create clones of your plants.

Propagation with seeds requires patience, care and some research. Seeds must be collected when they are fully ripe. They need to be cleaned, dried and stored properly. Hard, thick seeds often require a process called scarification which is a process of breaking the seed coat so that the seeds can absorb water and oxygen.

Propagating through cuttings is one of the easiest approaches for beginners. Many types of plants, both woody and herbaceous, are frequently propagated by cuttings. A cut is made with a sharp knife or pruners below where a leaf attaches to a stem, just below a node. The cut should be on a slant, which helps with water absorption. Sometimes, as people make a number of cuttings, they forget to pay attention to the polarity (distal and proximal ends) of cuttings. The distal end grows leaves and branches, while the proximal end grows roots and is the end that will go into water or into a rooting media (a substance that stimulates root development).

Spring through early summer is the best time to grow new plants from herbaceous cuttings made from more succulent non-woody plants, such as phlox, willows, geraniums and chrysanthemums. This is also the best time for softwood cuttings from fresh new growth on plants such as elderberry, sage and hydrangeas.

Late winter or early spring, before the plant breaks dormancy, is the best time to take cuttings from plants such as viburnum and dogwood, although later in the spring, when the plant is actively growing, can still work.

Another simple way to propagate is through division which involves separating plants into smaller sections, each with is own rooting system. Hostas, Christmas ferns and peonies are examples of plants that can be divided.
Layering is a method of division which involves encouraging roots to form on a stem while it is still attached to the parent plant. Examples of plants that can be propagated through layering include rhododendron, magnolia and winterberry.

The study of plant cell technology has led to more rapid and intricate ways of producing plants through other specialized methods like tissue culture and budding and grafting. Propagation through tissue culture cultivates cells, tissues or organs under sterile conditions using a prescribed nutrient culture medium (a type of recipe or “soup” in which plant tissue is placed). Examples of plants that can be propagated through tissue culture include philodendron, African violet and basil.

Budding and grafting are techniques used to combine one plant part with another to encourage growth of a unified plant. Grafting is common among fruit trees (cherries, plums, apples). Recently, grafting has also been used for tomatoes, giant pumpkins and watermelons.

It is important to gauge the amount of time and resources you are willing to deploy on propagating a plant. The right tools in your possession will enhance successful propagation. Some of the basic tools include pruning shears, containers and potting mixes, labels and markers, a water/ mist spray system, humidity dome, rooting hormone, and bleach or isopropyl alcohol (for sanitizing tools).

More detailed explanations for how to propagate using any of these methods can easily be found online, in gardening books or by reaching out to the Master Gardener Helpline: In New Castle County, 302-831-8862; in Kent County, 302-730-4000; and in Sussex County, 302-831-3389.

For information about master gardener workshops, visit udel.edu/master-gardeners and click on Garden Workshops.