Answer: Gardeners occasionally encounter trumpet vines (Campsis radicans) that refuse to bloom, andin some cases I suspect it may be a genetic variation in seed grown plants causing them to require reaching a more mature age prior to blooming. In other cases, the plant needs more sunlight (it prefers full sun all day, but I would think 9 hours would be enough assuming those hours include noon) or it has been overfertilized (an excess of nitrogen can discourage blooming) or it has been pruned too late in the season (and the blooming wood has been removed). This vine blooms on the current season's growth so it should only be pruned in late winter or very early spring. In my experience, trimming it back quite hard encourages it to bloom more profusely later that same season. You might try that and see if it helps.
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