Answer: Zinnia seeds can take from 10 to 24 days to germinate and prefer warm soils (70F degrees). Sounds as though some may still germinate within the next week or so. When the temperature is too cool, many seeds will sit patiently and wait - others will get angry and rot. You can watch to see what happens with the remaining seeds, but you'll probably have to sow some more when the weather warms up. Make sure that the seedbed stays moist, but not soggy, until your plants begin to grow.
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