Answer: Zinnia's should begin to flower 6 weeks after transplanting to a sunny location in the garden. (If you started them from seed they'd take 7 days to germinate and could be placed in the garden 4 weeks later. Add another 6 weeks, and they should start blooming.) If your Zinnia's aren't blooming by now, I'd suspect they're not receiving full sunshine all day (they love sunny spots), or they're planted in nutrient-depleted soil. Try fertilizing to give them some nutrition, and make sure they're in a spot fully exposed to all day sunshine.
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