My hydrangea bush hasnt bloomed in 3 years - What can I do?

https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/hydrangea-not-blooming.htm........eems like you are having alot of issues.....what are you doing with maintenance on your landscape

My one hydrangeas has these symptoms too. Im attributing it to the severely cold winter seasonal temperatures. My other hydrangea— very close by -but different variety -does bloom.

Non reblooming varieties of hydrangea

In summer, branches produce new buds for the next spring. These buds stay dormant all winter and bloom in spring. If winter temperatures got too cold, or if there is a spring cold snap that kills the buds, non-reblooming Hydrangea macrophylla will not produce flowers that year.

http://blogs.lt.vt.edu/mastergardener/how-to-choose-a-big-leaf-hydrangea-for-your-garden/

If this isnt the cause I would also be thrilled to figure out how to correct this problem.

Check the pH in your soil ... that is a major factor

If you drink coffee, drop your cooled used grounds at the base of the plant. They love it!

Remember to prune by mid August but don’t go too sever. Leave about two and a half feet of the bush. That way it doesn’t need to grown back from a stump before it can start putting its energy to putting on blooms.