Seeds
Many plants can be started from seeds very simply and will sprout in ideal conditions without much interference or help. However, some seeds require extra effort in order for successful germination to occur. Some seeds, such as those from Butterfly Bush (Buddleja davidii) are very small, and because of the smaller roots that they put down when they do sprout, they are more susceptible to dehydration. Because of this, they respond well to being germinated in a covered or partially covered container, so as to retain moisture until the plant has grown larger.
(Young Royal Poinciana Plant Grown from Seed after Soaking)
Other seeds have very thick, hard outer shells, such as those of Moonflowers (Ipomoea alba) and because of this tend to rot before they soften enough for the seed to sprout. There are a couple methods that assist with this situation. First, is scarification. Scarification is any process of breaking, scratching, or altering the testa (seed coat) in order to make it permeable to water and gases. This can be done easily using fine-grain sandpaper rubbed gently over the seed coat. Another thing that can soften hard seed coats is soaking in water, typically warm water. Alternatively, another method includes using retained moisture with sterile growing medium. I have experienced a lot of success using damp paper towels or tissues tucked around the seeds in question, and then sealed in plastic with a single, small vent for air. Moisture is retained, and the seed swells. The seed coat softens, and germination is easily able to occur.
Another notable requirement for certain seeds is that of cold stratification. Several species of plants require cold temperatures (34-41 degrees F), and often will not germinate without it -- many milkweed species (Asclepias spp.) are examples of this. This can be achieved by sealing seeds in a moist, sterile environment (such as a damp coffee filter sealed inside of a ziplock plastic bag) and keeping them between 34 and 41 degrees for approximately 30 days. Refrigerators work well for this, since they provide a relatively consistent temperature.
Cuttings
(Healthy Kiwifruit cuttings producing new foliage)
Another method of propagation includes taking cuttings from a mature plant in order to produce a new plant from the cutting. This can be done in a couple different ways. Many people use a rooting hormone (such as Rootone) to encourage roots to form, but many plants do not need this. While some cuttings may be placed directly into damp growing medium, I have observed the most success with placing cuttings in water to encourage rooting. This has worked well for Milkweed (Asclepias spp.), Butterfly Bush (Buddleja davidii), Allamanda (Dictamnus albus), Kiwifruit (Actinidia deliciosa), Hibiscus (Hibiscus rosa-sinensis), and many other various species. These were placed directly into water with leaves stripped from the lower portion of the cutting, and kept between 75-80 degrees F, and began to develop roots after a few days or longer. Once secondary roots developed, they were able to be transferred to soil successfully.
(Kiwifruit cutting - Actinidia deliciosa - developing roots)
Pups and Division
Many plants, such as bromeliads and irises, spread through either pups -- young plants growing from the base of the mother plant -- or by division. These are possibly the easiest plants to propagate, since they virtually do all the work themselves. For pups, simply remove the pup from the mother plant, usually by cutting between them in a downward stroke, and place the pup into soil. Keep the soil moist, and the pup will become established quickly. For plants that spread by division, the procedure is similar but the parts to be divided (the tubers, bulbs, roots, etc) are located underneath the soil.
Given that these methods have such a high rate of success, it poses the question: why are products such as Rootone, which are potentially dangerous to humans and other animals and damaging to the environment, used so popularly? Certainly many species were very successful at rooting without any hormone or chemical intervention.
Given that these methods have such a high rate of success, it poses the question: why are products such as Rootone, which are potentially dangerous to humans and other animals and damaging to the environment, used so popularly? Certainly many species were very successful at rooting without any hormone or chemical intervention.
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