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"How long will a seed last if kept well?"
I friend stole some seeds from his father's stash bag when he was in high school, my friend put them in a zip lock bag and thew them in a box in his closet. 10+ years later he gave them to me for my first grow. I had never germinated a seed before and threw them all in a glass of tap water, about 50-100 seeds. I got 12 in soil, all 12 were female.
So, if neglected but dry they last for a while.
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