Answer: Since you are obviously experienced at seed starting, the possibility that comes to mind first is that the soil temperature may have been too warm for the spinach to germinate; (it is also pH sensitive, although I would not expect that to be a problem in a commerical seed starting mix). Spinach is a cool weather crop and can be seeded outdoors very early -- even five weeks before the last expected frost, so this gives you an indication of how cold tolerant it really is. If your soil was warm enough to germinate tomatoes quickly (tomatoes prefer a warm soil!), then it may have been too warm for the spinach. If you have a question about the seeds themselves, you might wish to contact Burpee Customer Service directly at 1-800-333-5808.
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