Treating Seeds to Reduce or Eliminate Disease

Plants face all kinds of natural and manmade disasters such as hail, drought and pollutants. Another killer of plants is the many diseases that can infect them. A single plant disease can spread quickly, wiping out entire crops. There are, however diseases that can affect plants before they even get a chance to start to grow. These disease types attack seeds. Unlike plant diseases where you can sometimes see fungus or blight growing on a bloom, leaf or stem, seed diseases are virtually invisible. One type of seed that is more susceptible to disease than others is heritage seeds. Over the past 40 years, give or take a few years, companies have created hybrid seeds in order to prevent plant diseases. There are some farmers and gardeners, like myself, who prefer to grow vegetables using heritage seeds. If someone suspects that seeds may be infected, a hot water process can be used to help reduce or even eliminate the disease.

The hot water treatment is very affective in eliminating diseases in seeds because the hot water can penetrate the seed, killing the disease within. When using the hot water treatment, the gardener needs to know exactly what water temperature to use for which seed, because if the temperature is not right it could kill the seed or hamper its growth. It is best to treat a few seeds first and then let them germinate in a test environment before treating all seeds.

To treat seeds, place them in a cheesecloth bag along with a weight, such as a bolt, to allow the bag to sink, and be fully covered with water. The seeds are first preheated to 100 degrees Fahrenheit for ten minutes. The seeds are then placed in the appropriate temperature water for the appropriate amount of time (see list below). After the allotted time the seeds are removed, rinsed under cool tap water and spread out to dry, at about 70 degrees Fahrenheit.

Process broccoli, cauliflower, carrot, collard, cucumber, and kale at 122 degrees Fahrenheit for 20 minutes.

Process Brussels sprouts, cabbage, eggplant, pepper, tomato, and spinach seeds at 122 degree Fahrenheit for 25 minutes.

Process celery and lettuce seeds at 118 degrees Fahrenheit for 30 minutes.

Process radish and mustard seeds at 122 degrees Fahrenheit for 15 minutes.

Source: Master Gardener Classes