Cold windowsills are where a lot of sativa seeds fail, since the tropical lines want 25 to 28 degrees to crack reliably and will sit dormant or rot at 18. A cheap seedling heat mat under the paper towel plate fixes most of the slow germination people blame on old seeds. The germination temperature chart on
https://hazesativaseeds.com
compares crack times for Thai, African and Haze seeds at four different temperatures, and the difference at the cold end is dramatic. Warmth first, then patience.
