Simple Fall Plant Propagation Techniques
Hardwood & Semi-hardwood Cuttings
As a home gardener, fall ought to be a very special time for being productive in the garden. Autumn is the clearly the best season of the year to propagate plants, especially for home gardeners who don't have access to propagation misting equipment. The techniques that we'll discuss here are just as effective for deciduous plants as they are for evergreens.
Common practice in the past was to begin taking hardwood cuttings of evergreens after experiencing at least two successive hard freezes, which ensures the dormancy of the plant. However, based on the experience of Mike McGroarty, an expert plant propagation expert, it is most advantageous to begin propagating your evergreen cuttings even earlier. So in actuality, we will be working with "semi-hardwood" cuttings as opposed to true "hardwood" cuttings.
The only negative to beginning the cutting process early is that your clones will have to be watered on a daily basis unless you are blessed with regular rain showers. However, the benefits include significantly faster rooting which equates to stronger and higher quality rooted transplant material.
Your first order of business is to prepare an area in which to root your cuttings. Ideally, you are looking for an area of your yard that is shaded for about half of the day. Don't get discouraged though, as full sun will work equally as well. You'll just have to pay a bit more attention to your cuttings. The size of the area you choose depends completely on the volume of plants you want to reproduce. Realistically, each cutting should take up a single square inch of bed area, although you may need a bit more space for larger leaved specimens.
Start out by clearing the area of all grass and other vegetation from the area that you have selected. Next, build a simple wooden raised bed frame using four 2X4's or 2X6's nailed or screwed together at each corner and place it on the ground in the area that you cleared. You want it to be open on the top and open on the bottom, just a frame.
Next step is to fill the frame you just built with coarse sand. The sand should be clean, and much coarser than the sand one finds in a child's sandbox. Your best bet is to visit your local builders supply center and look at the various types of sand they offer. They'll probably have different grades that range from very fine to very coarse, neither of which you want to purchase. Ideally, you want to find something that is a little more coarse than their medium grade. Keep in mind, however, that it is not necessary to go to extreme lengths trying to find just the right coarseness. A medium grade sand will work just fine. Alternatively, bagged swimming pool filter sand works well and can probably be found at most home centers.
Once you have your propagation bed filled with sand, you are almost ready to start taking and sticking your cuttings. Thoroughly wet the sand the day before you start so that it will be possible for you to make a slit in the sand that won't cave right in. You can propagate virtually any kind of cutting, but good choices to begin with are the evergreens, Taxus, Juniper, and Arborvitae.
Take cuttings from the source, or "mother" plants, that are about 4 inches long and remove the needles from the bottom two thirds of the cutting. You can use virtually any sharp instrument to take the cuttings. Dip the stripped end of the cutting into a powder or gel based rooting compound and then stick that end into the sand just about an inch or so. Make sure the rooting agent you purchase is formulated for use with hardwood cuttings.
With Arborvitae, you can actually remove large branches and just tear them apart to get hundreds of cuttings from a single branch. By tearing them apart, you leave a small heel at the bottom of the cutting. The heel is a wounded area, which will actually produce more roots due to the stress caused by the wound.
After the weather gets colder and your area has experienced at least one good hard freeze, your deciduous plants will have dropped their leaves and should now be dormant. Now you can propagate them. As with your evergreens, just take cuttings about 4 inches long, dip them in a rooting compound formulated for hardwoods, and stick them directly into the bed of sand. Not all plants will root this way, but many varieties will. Luckily, it doesn't take much effort to find out what does and what doesn't propagate well.
The following varieties will all root well using this technique:
- Japanese Holly
- Blue Boy/Girl Holly
- Rose of Sharon
- Red Twig Dogwood
- Variegated Euonymus
Right after you finish sticking all of your cuttings thoroughly soak the sand with water to make sure there are no air pockets in the sand around the cuttings. Water your cuttings at least once or twice a day during warm weather. You don't have to water as much once winter sets in, but if your area experiences a warm dry spell, it is important to water during those periods.
Regular watering should begin again in the spring and continue throughout out the summer. By late spring, most of your cuttings should be rooted at which point you can cut back on the water, but don't let the bed dry out to the point that your tender seedlings die from lack of water.
The following fall, transplant your rooted cuttings into a growing bed and "grow them on" for a year or two, or you can just plant them in their permanent location. The entire process takes about 12 months, but it is simple and easy.
Michael J. McGroarty is a plant propagation expert responsible for the majority of the information presented in this article written by Jeff Edwards. You can learn a lot more by visiting Mike's most interesting website at FreePlants.com and sign up for his excellent gardening newsletter!