Answer: Sounds as though your Brussels sprouts were allowed to become overmature. Once they bolt (go to flower) they set seeds and die. That's just the nature of an annual crop. Sometimes unseasonably warm weather can hasten maturing of cool season crops. Next year check the seed packet to find the days-to-maturity and then mark the approximate date of harvesting on your calendar. That way, even if you're out of town, someone can harvest your sprouts.
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