I have a hydrangea vine, ten years old. I fertilize in spring, faces southwest, looks very healthy but has never flowered.
Hydrangea Vine With No Flowers
Certified GKH Gardening Expert
I would recommend having the soil tested. While there are many reasons a plant does not bloom, one of the most common is that there is an imbalance in the soil, typically too much nitrogen. Too much nitrogen will cause lush green growth with little to no flowering.
You can try to rebalance the nutrients with some phosphorous, which helps promote blooming.
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