Collecting flower seeds from your own garden or from other gardens where you've received permission saves money. If your seed gathering is the major way you obtain new plants, take a digital photo of the flower in bloom and include it in the labeled envelope with the seeds. Seeds should last for a few years if kept in a dry, cool place.
Inspect the seeds for mold or discoloration. Throw out any that are suspicious.
Place 20 seeds on a coffee filter. Spray the filter with water until it and the seeds are soaked. Fold the coffee filter in half with the seeds inside.
Put the coffee filter in a sealable baggie with a 1/2 teaspoon of water.
Place it in a warm, dark place. The top of the fridge works well. If you have a sunny window that feels warm to the touch, place the seed package in a paper towel inside on the window sill. The paper towel will block the light and keep the seeds in the dark.
Check to see if any of the seeds have germinated after 72 hours. You'll know because you'll see an embryonic root coming out of one end of the seed. The root will usually be white or cream colored, and very small. If you don't see one, add a bit more water and wait two more days.
Keep checking the package to see if the seeds have germinated. If after two weeks none have, the seeds aren't good anymore. If seeds have germinated, count them and divide by two and multiply by 10 to calculate the germination percentage. For example: 12 seeds have germinated out of the 20. Twelve divided by two is six. Six times 10 equals 60. The seeds have a germination rate of 60 percent.
Plant about twice as many seeds as plants you need to counter the 60 percent germination rate.