Plant Propagation, Part II
In my last column, I started a series on plant propagation, discussing seed production. This week I will cover some of the methods of vegetative propagation, sometimes referred to as cloning.
The reason we refer to them as “clones” is that they are exact genetic copies of the plant you are trying to reproduce. This is especially useful for plants that do not produce viable seeds. It also usually results in a mature plant more quickly than growing from seeds.
I will be describing several methods of vegetative propagation, but remember that not all plants can be propagated using any methods. Experience has shown that some methods work better than others for a given plant.
The first method I will mention is using cuttings. Here you are taking part of the plant, and inducing roots to form. Typically leaves, stem tips, buds, or stems are used. Stem tips are perhaps the easiest. With this method, the end of the stem, including the terminal bud, along with a few leaves is used. The stem should be 3-4 inches. Remove the leaves most distant from the terminal bud, making sure at least a few leaves are left. Then dip the end where the roots will grow in rooting compound, which is a plant hormone.
Moisten the rooting medium, place the stem in the medium, and place everything in plastic wrap to conserve moisture. However, do not put it in direct sunlight. After rooting, you will have a small plant with a good root system, ready to transplant.
The important thing to remember is not to let it dry out. Keep it moist, but not too wet, since you do not want fungal diseases to develop. This is true for the other types of cuttings that I mentioned.
Layering is another way of propagating plants. Some plants, such as brambles, do this naturally. Here, you encourage rooting on a stem while the stem is still attached to the mother plant. Types of layering include simple, air, tip, and compound.
Simple layering, sometimes called trench layering, is easy. Bend a branch to the ground and cover it with several with several inches of soil. Be sure that the tip of the branch extends above ground level. Make sure everything remains moist, and eventually new roots will form along the branch. Sometimes wounding may speed up the process.
The last method I will mention this week is division. Here, you are cutting or pulling apart the appropriate plant structure to produce new plants. The works best for some herbaceous perennial plants. The parts of the plants used may include crowns, bulbs, corms, rhizomes, tubers, stolons, or suckers.
If you have ever grown irises or day lilies, and needed to move them, you are probably familiar with this process. If they don’t break apart easily after you dig them up, you can cut them into more manageable sizes with a knife.
In my next column, I will cover plant propagation methods which require a bit more skill. These include grafting, budding, and tissue culture.