2006-09-28 / News

Propagating plants is easier than you think

By Roger Marshall

If you go to a nursery, you'll see a huge selection of plants with rows of identical plants of one kind or another. Most of these plants were propagated from older identical plants. You, too, can propagate plants to increase your stock of favorites or to get enough plants to make a hedge or border.

Depending on the plants that you want to clone, propagation is relatively easy. For example, I have a huge jade plant. All that is required to increase the number of plants is to take a small twig of the mother plant, push it into the ground and let it grow. There are a number of other plants that are as easy to grow as the jade plant. For example, Christmas cactuses can be propagated by breaking a small "leaf" off the mother plant at the division and pushing it into potting soil. Keep the mini leaf moist and it will usually grow. Many succulents are that easy to propagate, and most can be propagated at any time of the year.

Other plants may be more difficult to clone or may need to be done at certain times of the year for best results. They also may require different techniques to clone them successfully. First, lets look at various ways to propagate plants, and then we'll look at the times of year to do the work. Finally, we'll cover some plants that can be propagated.

Propagation techniques

There are three major methods of propagating plants. The first is by sowing seeds. The second is by cuttings, and the third is by dividing the roots. In each of these methods, there are special techniques that make it easier to propagate certain plants.

Growing seeds is a method that we are all familiar with. We simply sprinkle seeds in a pot or growing bed and wait to see what comes up. But some seeds require stratification - that is, they need to be put in a cold refrigerator for six or eight weeks and then in a warm spot, sometimes several times, before they will germinate. Other seeds require lots of light, mimicking

summer days, before they will germinate. Often these seeds can be tricked into germinating by putting them under grow lights for up to 16 hours a day.

Taking cuttings is another relatively easy method. Cuttings are best taken in August or September, before the new green sprouts have hardened off. The later you try to take cuttings the harder it gets. There are three methods of taking cuttings, too. You can take tip or stem cuttings. You can slice off a side shoot, called a basal cutting, or you can take a heel cutting by pulling a small branch off the main stem.

To take tip or stem cuttings, simply cut the plant tips taking two or three leaves, dip the cut end in rooting hormone and plant in soil. For good drainage, I mix equal parts of potting soil and sand to use as potting soil when I propagate plants such as fuschias, geraniums, pelargoniums, and other cuttings. These plants can be propagated right now so that you have strong young plants for next season instead of letting this year's plants get leggy over the winter. When propagating cuttings, it is essential to keep the potting soil moist. If you let it dry out, the new cutting will probably not survive. Professional growers mist cuttings regularly to ensure that they stay moist. However, if you let the soil or the plant get too wet, it will probably get mold and die anyway. When propagating cuttings, pare the cutting down to one or two leaves. That way not too much energy is being used by the cutting trying to transpire. On large leafed plants, some growers cut the leaf in half to reduce the area available for transpiration.

Another method of propagation is by root cuttings. This method is most often used for plants that have large root systems, such as chrysanthemums, irises, certain lilies, and bee balm or monardia. To make a root cutting of chrysanthemum, for example, simply dig up some roots, cut them from the main plant and replant them into pots. You can cut a single root an inch or 2 long if you like, and eventually it will grow into a larger plant. If the plant has deep roots, such as rhubarb or horseradish, dig out the entire root ball, and divide it onto sections before replanting them. This is best done right around now, when the plant is entering dormancy. Raspberries are another plant that can be propagated by digging the plant out and dividing it into rooted pieces.

While it isn't quite the same as dividing the roots, plants such as rhododendron and privet are propagated by rooting a low growing branch. In the spring, simply take a low branch, cut it about the way through on a slant, and push the cut into the ground. Wedge the cut portion under the soil or put a brick on it to hold it down, and let it grow. It doesn't take long to get a new plant rooted. Once the plant is growing on its own, cut the branch connecting it to its parent.

Propagating is not too difficult. It requires a little patience and luck, and you can increase your stock of plants without spending a ton of money. If you want to try propagating, take some cuttings from your indoor geranium plant, dip them in rooting hormone and put them in potting soil. If you keep them just a little moist, they'll grow. Have fun!

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