Rooting tonics, also called rooting hormones or rooting compounds, are products that contain plant growth hormones used to stimulate root growth during plat propagation. Many commercially-sold rooting products contain a synthetic form of indolebutyric acid. If you have access to a willow tree or shrub, you can easily make your own rooting tonic, because indolebutyric acid occurs naturally in all varieties of willow trees.
- Collect approximately 2 cups of willow branches or 3 cups of bark.
- Choose small, young branches that are no thicker than a pencil. The highest concentration of hormone exists in the youngest branches.
- You can also use bark from live older willow branches or trunks. If you go this route, you need to use more bark because it contains less hormones.
- Do not gather old dead branches from the ground, as they will contain very little indolebutyric acid, if any.
- Cut the willow branches into pieces between 3-to-6-inches long. If using bark, cut it into 2-to-4-inch pieces.
- Put the willow into a pan or bowl that is large enough to hold the clippings plus a gallon of water.
- Boil 1 gallon of water and pour it over the willow clippings.
- Allow the willow and hot water to brew for 12-24 hours.
- Pour the liquid into glass containers with lids that close securely and discard the pieces of willow. You can store the tonic in the refrigerator for up to two months.
- Use the rooting tonic when propagating new plants.
- Soak the tips of your cuttings in the rooting tonic for several hours before planting them.
- In addition to encouraging the growth of a strong root system, the willow rooting tonic inhibits the development of bacteria, fungus, and viral disease.
- Honey may also be helpful as a sanitation agent, although it contains no hormonal advantage. Dip the cut end of the plant in the honey and then put it in the soil immediately. Alternately, you can boil 2 cups of water, add 1 tablespoon of honey, and soak the end of the plant for several hours before putting it in the soil.
- Add approximately 1/2-cup willow rooting compound to 1 gallon of water and use the mixture to water the young seedings during the first few weeks of growth.
- Some people have reported success using aspirin as rooting tonic. To try this method, dissolve an uncoated aspirin in 1-cup of water, then soak the cut end of the plant in the water for several hours before planting.
- In a 2007 U.S. Department of Agriculture study, a diluted solution of 1.3 teaspoons of hydrogen peroxide in 1 gallon of distilled water was found to control disease in plants and cuttings. Growth and flowering benefits were seen in nasturtiums irrigated with the solution. Use the solution as a dip for cuttings to promote sanitation.