Answer: Plant maturity is generally the reason for blooming/not blooming. Although they are the same age, one plant has grown up faster than the other. Even though the planting sites seem identical, there may be a microclimate where the smaller plant is living. Or, it might be that its root system just hasn't been able to grow as large as the other's. Could be the soil, or some hardpan a foot or so down. In any event, as long as it looks healthy, it will eventually catch up to its sibling. Just be patient with your plant and enjoy your garden!
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