Answer: Based on your description, I am not certain what the problem is but, if the location is poorly drained, it is possible the soil is simply too wet. Another possibility is that the occasional truly cold night has just been too cold for them without protection. Finally, while the soil temperature does need to be over about 35 degrees for the seed to germinate, it does do better in a slightly warmer soil with optimum germination around 70 degrees. You still have time to seed again for spring.
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