The late Dr. Bob is the father of Montana’s Master Gardener program. When he taught the classes nobody ever fell asleep. He was a writer of a great many articles on gardening. The following is just one of several hundred in my files.
A question to Dr. Bob: “How can I increase germination of my garden seeds?” (March 2002) Gardeners all over the country are right now wondering how to get better germination in the vegetable and flower seeds. Of course, start with good seeds and in most cases you’ll have good germination, but some seeds are notoriously tough with hard seed coats. Now, researchers in Georgia have found a common household substance that increases germination in watermelon seeds.
The seedless watermelon cultivars on the marker are for the most part, triploids. That means that they form fruit that has no developed seeds. While they are no good for seed-spitting contests, the melons do make great eating. The triploid cultivars are expensive to produce and, unfortunately, the seeds have thick coats that interfere with germination. Researchers have found that soaking the seeds in 1 percent solution of hydrogen peroxide at room temperature and in the dark greatly improves their germination. After just a day or two in the solution, the seeds germinated readily in petri dishes and would no doubt do so in the garden soil.
The 1 percent solution does not damage the emerging radicle, but solutions two percent or higher do severe damage to the young seedling. The hydrogen peroxide is generally available in the drug store and is a three percent solution, so you must dilute it with water. You can do that by adding two parts water to one part hydrogen peroxide. So far, researchers have only tested the solution on watermelon seeds, but they suggest that it might also improve germination in a wide range of “hard-coated” seeds, such as those of cabbage and broccoli.