I moved into a new home about three years ago. The first summer I just let everything grow just to see what was there. I have two big hydrangea shrubs on the west side of the house. The first year, I let it do it's thing. No blooms and no pruning. The second year I have tested the soil, added fertilizer. Still no blooms. I pruned the dead sticks away early spring (and they were just hollowed sticks that snapped off), added hydrangea feed and still nothing! I have a small one I planted in the front of the house last summer that had blooms on it when it was planted. This summer it has done beautifully. I am wondering if the west side of the house isn't providing enough sunlight to help with blooming, but the leaves are big and beautiful. There is a pine tree that has gotten much larger than when I first bought the house and I am sure it's blocking most of the setting sun. The attached photo was taken at 6 pm. Any insight?
Adding fertilizers with high phosphorus, and potassium levels will promote bloom growth. Here is an article that will help: https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-not-blooming.htm
They prefer full sun in the morning, with some afternoon shade; however, many will grow and bloom in partial shade.