Sunflower (Helianthus annuus) seeds, whether purchased or saved from your own garden plants, lose viability the longer you store them. Age, storage conditions and temperature can all cause the seeds to expire before they sprout. Checking the seeds for viability before you plant them in the garden helps you know how many seeds you need to plant or whether it's time to start over with fresh seeds. Test seeds about two weeks before you plan to plant them for the garden.
Stack three paper towels on top of each other. Wet them until they are thoroughly moistened and lay them on a small plate.
Set 20 sunflower seeds on top the wet paper towels. Cover the seeds with a triple layer of moistened paper towels, sandwiching the seeds in between.
Slide the plate into a gallon-size plastic bag and seal it closed. Set it in a warm 70-degree-Fahrenheit location. Check the towels daily and mist them with water if they begin to dry.
Remove the bag and top layer of towels after seven days and check for sprouts. If few seeds have sprouted, wait for up to seven more days, for a total of two weeks.
Count the seeds that sprouted. Divide 20, the number of seeds checked, by the number of seeds that sprouted to determine the germination rate. For example, if 10 seeds sprout, you have a 50 percent viability rate and must plant twice as many seeds as desired plants to ensure enough seedlings for the garden.
Things You Will Need
- Paper towels
- Spray bottle
- 1 gallon plastic bag
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