Should the medium covering the seeds dry out, water lightly until the flat drains. This temperature can be maintained by the use of a thermostatic heating pad. Have students plant seed into flats according to the guidelines above. Experiment with different planting depths, seed coverings, and germination temperatures. Seed should be fresh, and should have been stored under cool, dry conditions.
Seed loses viability as it gets older.
Geminating seedlings are very susceptible to drying out as they have no root system to supply moisture. In the field, seed will not germinate if planted too early in the season when night temperatures are too low. Seed planted too shallow will dry out. These are concerns mainly when germinating seed in the field. Compare differences and germination rates in the same variety of seed manufactured from competitive seed companies.