Answer: Sounds like heat is not your problem since you have tried both cool and warm soil. (According to the American Horticultural Society, 55 degrees F is ideal.) Delphinium seeds require darkness to germinate, so be sure to cover them lightly with soil. Germination normally takes 10-20 days. What about cold stratification? Are you sure the seed company has done this? If you are not sure, place the seeds in the freezer for 5 to 7 days before planting. If you have done all this and still have zero germination, then it's likely the seeds are not good.
If the seeds are packaged for 2000, then, yes, they are fresh. You might try a germination test: place some seeds between two moist paper towels, and place in a loosely tied plastic bag. Keep the paper towel moist, and check the seeds every few days for signs of germination. If these seeds fail to germinate, contact the supplier to see about replacement seed. (If you purchased the seed from Burpee, contact their customer service department at e-mail: firstname.lastname@example.org or call 1-800-333-5808.)
Q&A Library Searching Tips