June...the perfect time to make new plants

-A A +A

    Tom Woods 

Master Gardener

One of the easiest ways to produce a new plant is to take a cutting. This is a type of asexual propagation that creates a clone of the plant you wish to reproduce. The new plant will be identical to the parent plant. Propagation by cuttings involves rooting a severed piece of the parent plant.

Herbaceous cuttings are made from non-woody, herbaceous plants such as coleus, chrysanthemums, and dahlia. A 3 to 5-inch piece of stem is cut from the parent plant. The leaves on the lower one-third to one-half of the stem are removed. A high percentage of the cuttings root, and they do so quickly. These cuttings can be placed in a glass of water and will develop roots over a period of time. Some cuttings, such as red dragon fleece flower (Persicaria microcephala) or coleus will root in a week; others such as Angle Trumpet (Brugmansia) can take several weeks to root. Once the cutting has established plenty of roots, you can pot it up and allow the roots to get further established before including the new plant in your garden or giving it to a friend.

Softwood cuttings are prepared from soft, succulent, new growth of woody plants, just as it begins to harden (mature). Shoots are suitable for making softwood cuttings when they can be snapped easily when bent and when they still have a gradation of leaf size (oldest leaves are mature while newest leaves are still small). For most woody plants, this stage occurs in May, June or July. The soft shoots are quite tender, and extra care must be taken to keep them from drying out. The extra effort pays off, because they root quickly. 

The best moment to take softwood cuttings is when the leaves are turgid, but not hard or leathery. On the day of collection, begin early in the morning, when the plants are filled with moisture not yet lost to the sun and heat. Use a sharp knife or pruning shears that have been dipped in rubbing alcohol or a 9:1 water and bleach solution. Carry your cutting tool and a bucket of water for the cuttings. At the lowest part of the softwood, where it sprouted from a bud, the growth should be firm and just starting to darken in color. Make the cut just above this point where the new growth begins. Plunge the cutting into the water where it will remain until you are set up for the next steps. 

Trim off the lowest of the side leaves and make a new slice, cutting on an angle, across the bottom of the stem. A quick dip of the stem into a hormone solution or powder is the next step. Put a small amount of the rooting compound in a separate container before treating cuttings. Any material remaining after the treatment should be discarded. Carefully tap the cutting to remove excess hormone when using a powder formulation. Use a sterile soil-less potting medium placed in a small but deep pot (a large styrofoam cup will do) with a hole in the bottom. Use a clean, thin stick to make a hole in the potting mix and insert the cutting one-third to one half its length in the cup with the buds pointing outward; water again after inserting the cuttings. Place the cup with cutting into a zip lock plastic bag, close the top and place the bag in a cool place out of direct sun.

Rooting times vary with the type of cutting, the species being rooted, and the environmental conditions. After a few weeks, you can test your cuttings by gently tugging on the stem. If it resists your pull, roots have formed. Once roots are established, you can repot your new plant to a larger container to allow the roots to become well established. Plants that I have successfully rooted this way are: acuba, gardenia, Daphne, pittosporum and Illiciam floridanum. Many shrubs can be propagated by this method.

Semi-hardwood cuttings are usually prepared from partially mature wood of the current season’s growth, just after a flush of growth. This type of cutting normally is made from mid-July to early fall. The wood is reasonably firm and the leaves of mature size. Many broadleaf evergreen shrubs and some conifers are propagated by this method. The procedure for taking these cuttings is similar to that for herbaceous and softwood cuttings, but the treatment is not.