I just rechecked the hydrangeas. The first stem has a stem that isn't wilted yet but it's stills green. The wilt is only on stems that have changed color. Could this still be root rot? The stems are all still healthy and the first plant has been like this for a few weeks now. It hasn't died but the leaves still cling to it.

Your post gives no clue as to your Latitude, so your plants may be right on schedule. Al

IME, this is NOT how oakleaf hydrangeas should look at this time of year. The color change is perfectly normal - the wilting is not. Even when going dormant, the plant will retain a certain degree of turgor and the leaves tend to retain this look well into winter. In my climate, they will look good - colored but good - all winter until new growth in spring pushes them off. There is little, if any, sign of wilt all winter long.

This looks suspiciously like a water issue in my opinion - either too little or too much, possibly leading to a root rot.

Im sorry I didnt post my zone...Im not sure why it doesnt show up when I post. I am in zone 6 on the A/B line in CT. It has been cold here and most trees have either lost their leaves or are about to.
I was worried this could be a rot. I did dig up the first plant and the roots seemed fine. This is in a very well draining spot. I dont think I have over watered. What would the roots look like if they were rotted? They seem normal to me but I am not sure what I am looking for.
The drooping only occurs on branches that have colored up. The first plant still has 2 stems that have all green leaves and those leaves are not wilted.
I normally would not panic and let it be but I am afraid that it could be something that could spread to my other plants.
If it was a root rot or some kind of pathogen, how long would it take for the stems to die? As of right now the stems are plump, firm and healthy and I see no signs of damage anywhere on the stems or base of the plants. What should I look for?

That first photo, the one that looks completely wilted, it has two stems on the other side that have all green leaves and those leaves are not wilted yet. just trying to clarify because my post seems confusing. The wilt is only on stems that have colored up.

You always have to think root rot with oakleafs when you see wilting. I lost an Alice many years ago due to an El Nino Year in which we were pummeled with 2-3 rain storms per week, each delivering at least 1" of rain at a time.

If it is root rot, damage from excessive watering probably occured during the last few months not just recently. I am guessing on that because you sound so certain that the shrubs have not been overwatered. Hard to estimate when a problem happened or started. So try to water when the soil starts to feel as if it is almost dry or when dry.

That being said, I have a Pee-Wee which was turning from green to reddish/purplish colors one Fall too. The temperatures went down one day below freezing, but not much and not for long, Like yours, some of the red leaves wilted, dried out and.... that was it. The green leaves were not affected. They changed colors and eventually dried out later. No other visible damage happened then or by Spring. And it has not happened again. So, I hope that nothing will occur to your shrubs. Keep a vigilant eye on the shrubs' watering & soil moisture in case this is root rot.

I suggest you be on the lookout for watering issues as soon as the temperatures in Aug-September go down and stay down. During that transition, plants sometimes get exposed to too much water because while temps go down, we do not tweak the sprinklers & drip systems to deliver less water rightaway.

If you are extremely concerned, feel free to send leaves and soil for analysis at an agriculture extension service office.

Luis