For the germination test, usually ten seeds are used. The germination percentage is figured by multiplying the number of seeds that sprouted by ten. I will use the seeds if the germination rate is 80% or better for seeds started in the hot bed. Small seeds like lettuce and carrots, which I’ll probably plant too close anyway, 50% is the cutoff. All others it’s 70%.
I use two methods to test for germination. The quick and easy way is to moisten a paper towel and count out the ten seeds while the towel is spread on the counter top. I can get about three different types of seeds on each towel. I then fold the towel over the seeds a couple of times. I them mark the seeds by writing the names on a dry paper towel and folding it over the damp towel so the name is over the correct group of seeds. These towels are then carefully placed in a bread bag, squeezed to remove some air and then tied on the open end. I check them in two weeks to assess the progress. If germination is good I do my calculations. If germination is poor I reseal the bag and check them again the next week. I feel that three weeks is sufficient time for this test.
The second and most interesting method is to plant the seeds in potting soil and watch the progress. I often use the “cup sized” peat pots
I use five seeds in each and multiply by 20 to get my percentages. These should be kept fairly moist but no soaked and not real close to a heat source. Labels can be placed under each pot. A variation of this method is even more exciting. Try using flower boxes with potting soil. I like planting fast germinating seeds (beans) next to slower germinating seeds (carrots) just for fun. I’m usually able to get ten seeds per area here. If I get the lettuce or carrot seeds over planted (due to the small seeds), I just observe how thickly they sprouted as my guide. I use those little plastic markers to label each group of seeds. These can be observed often without disrupting progress. Again, three weeks is the limit.