Answer: None of my references indcate that sunflowers (Helianthus) are daylength sensitive, as are strawberries and onions. It may be that there is an soil nutrient imbalance or some other stress that pushes the plants to flower before they are full grown. Areother plants in your garden performing okay? Sometimes stress can cause plants to rush to flower. Are your sunflowers getting plenty of nutrients, water, and sunshine? Also, check the variety you are growing--there are lots of new dwarf types so be sure yours is the "real" thing. Your county extension office might be able to help you pinpoint the source of the problem (ph# 305-248-3311).
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