Answer: Although tolerant of a wide variety of growing conditions and stress, these trees (Cotinus coggygria) flower best when planted in a full sun location and grown in average to better soil with adequate moisture as opposed to drought conditions. When growing the straight species, there is a certain amount of variation betwenn individual plants so that some bloom better than others, some have better fall color than others, and so on. If this is what you have, you might simply have a poor performing specimen due to seed variations. Among the named cultivars, some were selected for foliage color rather than flowering attributes, so this could also account for the poor flowering performance. Finally, in my experience, most of these plants in the landscape just do not really live up to their name so try not to have an overly high expectation.
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