Plant Pathology Infobytes
April 10, 1996
Start Right With Healthy Vegetable Seed
Vegetable gardeners are fully aware that trying to figure out what type of early season growing conditions to expect can be tricky. The best approach is to get started right in the hope that the weather will cooperate. One of the best ways to reduce the chances for early season gardening problems is to use healthy seeds.
Whenever possible gardeners should start each season with seeds from a commercial source. This is particularly true if you had problems with diseases last season, since seeds saved from diseased plants often carry fungi, bacteria, and even viruses, which could become seed-borne and cause problems in the new crop. So it's generally unwise to save vegetable seeds from season-to-season.
Examples of seed-borne diseases are anthracnose of lima beans, early blight of tomatoes, mosaic virus of Southern peas, bacterial blights of beans, black rot of cabbage, and leaf spots of turnip and mustard greens.
To help prevent diseases of this type, your garden store will have available seeds that have been produced under stringent guidelines to insure that seeds are free from diseases. Often seeds originate from dry regions, such as the Western United States, where diseases are less common.
After good seed have been selected, the next step is to make sure the seeds are properly treated with fungicides. Seeds from dealers are often pre-treated with fungicides such as captan or thiram to help control seed decay and damping-off diseases. Look for red or green colored seeds, which indicates seeds have been treated with a fungicide.
The use of treated seeds is especially worthwhile when seeds are to be planted early season in cool, wet soils, conditions which are favorable for development of seedling diseases. Fungicides applied to seeds reduce seed rot and give some protection from seedling disease during early stages of seedling development.
If you do have "homegrown" seeds you plan to use in your garden, you may carry out your own fungicide seed treatment. Large seeded crops such as corn or beans can be treated by placing seed and fungicide in a quart or pint container and gently shaking or rotating the container until all seeds are evenly coated with fungicide. As little as 1/2 teaspoonful of captan or thiram per cup of seed is an adequate amount for treatment.
Smaller vegetable seeds may be treated directly in the seed envelope by adding the fungicide to the container, resealing, and shaking gently. Only a small amount of fungicide (1/8 teaspoonful or so) will be needed.
Be sure to wash equipment and hands after handling fungicide and treated seeds. Treated seeds should be planted promptly.
For additional information on getting started right in the garden, check with your county Extension office.
Infobytes newsletter was written by the late Dr. Frank Killebrew, Extension Specialist.