| Hmmmm...good question...you have 2 plants, the same cross, presumably the same age, one blooms the other does not.....
Are the 2 plants mericlones? or seed grown? If seed grown, that could be the reason as sibling plants, even of the same cross do not always grow and bloom the same. If they are mericlones, and therefore nearly exactly alike genetically....I'm not really sure what the difference might be.
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