Plant Stimulants

How is Vitamin B-1 used in a garden? Don't waste your time with Vitamin B-1; it has proved a failure under most conditions.

What is gibberellic acid? How does it affect plants? Gibberellic acid is a growth-stimulating substance produced by a fungus that attacks rice plants and causes them to grow rapidly for some time before the fungus finally injures too much of the tissue. When applied to some plants, a 10 part per million solution of gibberellic acid in water will stimulate a marked increase in rate of growth - especially in the length of stems and petioles. This stimulated growth is sometimes attractive and sometimes not. Gibberellic acid often hastens flower maturity and, in some instances, it increases flower size. Dwarf varieties of a given species usually respond most markedly to gibberellic acid. Standard sorts respond less, and giants are generally unresponsive. One of the interesting and perhaps most valuable properties of gibberellic acid is that overcoming the dormancy effect in some plants and seeds. Except for its use as a seed stimulant, gibberellic acid is a research tool rather than an everyday useful chemical.

What is colchicine, and how is it used? An alkaloid from colchicum is used by plant breeders in attempts to change inherited characteristics of plants by doubling the chromosomes.

Where can I acquire colchicine? From drugstore or local chemical supply houses. It is a very poisonous substance; must be used with caution. Comes in paste or solution, which is applied to top buds of shoots of plants. Of some use to plant breeders, not to average gardener.

I desire information concerning "hormones." Hormones (more properly called plant-growth regulators) are useful for reducing the time required for some cuttings to root. Most all of them are dusts in which the cutting is dipped. Some are sprayed on developing fruits to prevent drop. Some are sprayed on flowers and thus produce fruits without pollination (tomatoes, holly, etc.). Some are used to increase keeping quality of fruits and vegetables in storage.

Is there anything to the theory of enrichment of the soil with chemicals to include all those needed by the body? If your entire food supply comes from a given plot of ground, this is important, but the varied diet of the average American means it has little significance.