Pleasing plant propagation, Part 1

By Tim Baker, MU Horticulture Specialist
Occasionally, someone calls me with a question about propagating a plant that they really like. Can they save seeds and plant them? Or, should they try cuttings or grafting?
Some plants are easy to propagate, and may have several alternative methods. Some are more difficult, and may have an optimal way of propagation, with very specific steps. So in my next few columns, I thought I would introduce you to the world of plant propagation.
Before I start, let me give one caution. Be sure that it is legal to propagate your plant before you try. Some plant cultivars are protected by patents, and propagating them, even for home use, is illegal.
There are two basic ways that plants can be propagated: seeds and vegetative propagation. This week, I will cover seed propagation.
In many ways, propagation by seeds is the easiest. However, some species do not produce viable seeds. In addition, other plants produce seeds that may not produce true-to-type offspring. In those cases, vegetative propagation may be your solution.
What do I mean by “true-to-type”? Seeds are the end products of properly pollinated and fertilized flowers. If all goes well, these flowers will eventually produce a viable seed.
Some plants have flowers that are self-pollinated. These are usually safe to save seed from, and will result in offspring that are the same type as the parent.
However, some plants must be cross-pollinated, by a different cultivar of the same species. When this occurs, there is a mixing of genes. This will result in an offspring that has traits from both parents. Thus, the offspring may not be the same type as the parent plant you were interested in propagating. Apples provide a good example of this.
Hybrid plants are another example where saving seed is not a good idea. These plants are the products of two inbred lines of parent plants, and while the initial cross (the F1 generation) produces uniform plants, the seeds produced by those plants are not genetically stable. That means that offspring from those plants probably will not be true-to-type.
If the plant that you want to propagate from seed passes all the above tests, and is not patented, then you have an excellent candidate to save seed from. You may need to take special measures to insure that cross-pollination does not occur, to keep everything true-to-type.
Also, be sure that the seed is mature. Seeds from green peppers, for example, usually do not germinate well. You need the pepper to color up and be mature, perhaps to the point of being over-ripe, for the seed to have good germination.
Many seeds are dormant when first produced by the plant, and will need special treatment to germinate. Some, for example, need a period of chilling before they will germinate. Others may have a thick seed coat, which must be broken so that they can absorb water and germinate.