which may be natural dying at the end of the season.

===>> mid august is not the end of season ... especially in zone 7 ...

the top down pic is not helpful ... could we have a pic of the whole plant from the side ...

whats the weather been.. drought ... etc ...

though its not the end of the season.. a lot of things start looking beat up this time of year ... if you understand the difference ...

ken

You may have a touch of powdery mildew on some of the leaves in picture 2 but the leaves are too distant to tell for sure.

Picture 1 does not show the soil mulched so I would add some organic mulch (no rocks). A few yellow leaves in the summer would be ok but just "a few".

I would water the soil (never the leaves) at summer time levels until temperatures drop below 85F on a regular basis.

While mulching, I would inspect the plant for insects/pests but be aware that some are only visible at night while others, like spider mites, are very tiny.

Here are some more pictures, hopefully more helpful.

At some point I suspected I was overwatering so I stopped and left it mostly to the rain, which we had a bit here and there. The mop hydrangeas left and right of her, who received largely the same treatment are doing great. Yes, I need to add some extra mulch but I doubt this was the problem.

I was hoping it would come back but it continued its decline. The first symptoms appeared with yellowing on the edges of the leaf, as the second picture above shows.

I could not see again the grayish marks of powdery mildew on the new pictures so, if you don't see them either, hopefully that is not the problem.

Did you check for insects that might like to chew the leaves to suck the leaves' sap (spider mites, aphids. etc)? For spider mites, you can put 8.5x11 white paper around the crown (where the stems originate from) and shake the plant to see if any "dots" that move fall down onto the papers. I did not see any hints of insects in the pics but spider mites are too small to be seen many times. Some pests only come out at night.

Over-watering cam prevent the roots from getting the minerals that the plants need. To know if the soil is current too wet, (a) insert a finger into the soil to a depth of 4" and see if it feels wet or (b) get some soil in between two fingers, press and see if you see water droplets forming (that would indicate that the soil is too wet too). Can you try those and let me know what do you detect? I assume your soil is still as acidic as mine was :o) when I lived there?

We have not discussed if you have fertilized or amended the soil... to rule out those as causal agents or complications (your leaves are not as dark green as they should be... unless it is a camera issue or my monitor). Prior to the start of the symptoms, did you do something like fertilize, amend the soil, chemicals, etc?

I assume you have not observed any orange pustules on the underside of the affected leaves?

How has the weather been by you? Could you poke around in the soil near the base of Annabelle and see how the soil is - wet, dry, compacted, loose - down a couple inches? It looks like she is in a fairly small strip between the lawn and the deck/porch - how wide is that strip? What is the soil like under the deck?

lisanti,

She is indeed in a narrow strip between the deck and the lawn. The soil is Georgia clay with a bit f amendment that I add in spring.

It feels compacted, like all soil around here, but slightly damp, as it should be with occasional watering. It is neither soaking nor dry. The soil under the deck is also GA clay.

The weather has been hot, as any summer, 90's or so - but we've also had some rain, not too much, more like normal.

As I mentioned, about 1-2 months ago I think I was overwatering - but then I stopped. Yet it continued to decline, maybe because the damage was already done? I don't know.

It's very hard to tell under the circumstances.

Over-watering can flush many nutrients away but usually this happens in
container plants. Fertilizers are usually not something you want to add
to a plant that is stressed but you can try to add back some of the lost
nutrients slowly with a weak fertilizer like fish emulsion, liquid
seaweed (they contain lots of nutrients other than the usual npk) or a
fertilizer at half the label's strength. Have you had time to check some
of the things I suggested?

Hi Luis,

I checked for insects - none.

I checked the soil and it is only slightly damp. Definitely no water droplets or soaking - but it just rained yesterday.

No orange pustules on the underside of leaves.

I fertilized the soil in spring with some Hollytone and I also added some soil acidifier because the mop hydrangeas left and right are purple, which suggested the soil may be slightly more alkaline than it should be. I want them blue so while I was at it, I also added some of that acidifier to Anabella even though I know her color will not change.

My mops were still on the purple side this season so I couldn't have possibly added too much acidifier.

That's all.

I don't have any of those organic fertilizers (fish, seeweed, etc) but perhaps I could get away with some water-soluble from Proven Winners? It has iron in it - and I read that helps with yellowing of leaves sometimes.

I don't fertilize the Annabelle I've got, out of fear that she would then attempt world domination - this plant is a beast, which is why I can't figure out why yours looks so sad. I think that your plant does not have enough room to get its roots spread out, particularly if that thin black strip is one of the six to ten inch lawn borders (I've got the ten inch, but not near Annabelle). She is also not getting much air circulation around her, with the lattice so close behind her.

lisanti,

Then I wonder why the other two next to her seem to do well?

Indeed, Anabelle grew much smaller than I expected, based on what I'd read.

"I also added some of that acidifier to Anabella even though I know her color will not change." - I usually water the plants before fertilizing or amending the soil with aluminum sulfate to prevent injuring/burning thin shallow roots on a dry plant.

Maybe that explains it. Well, too late now. I hope it doesn't die. She seems to be hanging in there but she's stunted, with yellow leaves.

The mop hydrangeas are different plants, with very different needs. Annabelle needs space, much more than the mopheads.

Severe, did the hydrangea perk up after all the soaking?

Thank you for checking in, ophoenix! I decided to give it a bit more time as digging it up now does sound a bit drastic. It's been planted there in the clay soil for a few years and it would require quite a bit of digging to remove it.

I don't think it was a water issue as it has received plenty throughout the season. It does get some nice morning sun, I am not sure if half a day though - and the other mop hydranges that flank it don't really block the sun. All three get about the same amount. It's been fine for 3 years and I am not sure why this issue would have shown up now.

If anything, I think I may have overwatered it earlier in the summer and may have washed away some nutrients in the soil. I haven't yet tried the advice I got earlier, to apply a bit of water-soluble fertilizer, but I am thinking to tey this first.

It hasn't gotten any worse but it looks the same - kind of stunted with yellow streaks on the edges of the leaves.

I recently ended up with what looks like a new mop hydrangea from a shipping error where a nursery sent it instead of a rose I'd ordered; when they fixed the problem they allowed me to keep the hydrangea.

Well...perhaps I should plant this new mop in Annabelle's place, between the other two mops? I don't even know what color it is - my other two bloom purple.

Maybe I should dig up Anabelle, as you advised here, and then try to find her a sunnier spot?

Not sure yet where that would be as sunny spots are rather hard to come by on our property. But I may be able to find something a bit sunnier than where she is right now.

Hmm...maybe that's the way.

Sounds like a plan for you. I know people talk all the time about over watering hydrangeas, but I found if the plant has good drainage that is not a problem. It is a problem however if the soil does not drain out of the root ball area. The only way to know for sure - and end trying a bunch of other suggestions from others - is to dig it up and check the root ball! Work? yes but it just depends on how much you are willing to do to find out the reason the plant is not thriving. I would bet that it will not be a problem at all to dig it up. That you will find a root ball that is so tangled that the water can not penetrate it at all. If you plant without loosening the roots from the pot it was grown in the roots will continue to grow in the direction that they were growing in the pot. So, if it was at all root bound - that is what it is called - it will continue to be root bound even though it is in a hole in the ground.

Three of my one year old cuttings were doing beautifully and we had a very hot spell and they were missed when we watered. They got totally fried! I took off the fried leaves, cut back the worst of the dead looking little branches and put the pots into containers of water up to the rim. They stayed there for 5 days! Soaking! and all came back just fine. They are all leafing out, and will be just fine next spring after their dormancy.