Established Hydrangea stems wilting and dying

Question

When I bought my home 6 years ago, the hydrangea was already there. It was about 4-5 feet tall and almost as wide with beautiful blue mop-head blooms. Everything was fine until last year. I noticed the stems were leafing out, but on some stems, the leaves were wilting and then the entire stem would die. It is worse this year. It has more dead stems than live. The stems that have leaves are producing flowers. The only change at the site is a tree that could be giving it more shade. It gets morning sun and afternoon shade. I live in the southern part of Mississippi.

Answer 1

Hydrangea commonly will droop if they are unhappy or even during the hottest park of the days.
Check the moisture level in your soil. Even though they are established, they may need to be watered more frequently.
Here are some articles that will help you.

https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/drooping-hydrangea-plants.htm
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/prune-hydrangea-bushes-hydrangea-pruning-instructions.htm
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/fertilizing-hydrangeas.htm

Answer 2

Thank you, downtoearthdigs, for replying to my question. I am not sure if my question was answered. It is only certain stems that wilt, not the entire plant. Plus it happens in the spring when the weather is cool and the rain is plenty. The rest of the plant is fine; the leaves on some stems are not wilted when other stems are wilted. By the time the weather is hot and rain is not as frequent, the wilted stems are dead. Would certain stems wilt and die, when other stems are fine/beautiful and have never wilted?