any hope for my hydrangea?

Have I ruined this plant beyond repair? :(
Bought it recently, repotted it into this large pot with compost, have been watering it pretty generously. It's on my roof terrace which is east facing and so it does get quite a lot of sun during the day.

Give it some shade during the hot afternoon and it will do fine. You can prune the flowers off if you wish and any old, damaged leaves as well. I see lots of new leaves coming on so it seems to be okay.

The Hydrangea required a much cooler space than on a roof terrace, in fact most types of these plants (and there are very many) like good light BUT dont like direct blazing sun for long periods of the day.
I would remove it from the terrace, place it in good light but NOT direct sun for summer, they do like a lot of water BUT maybe not as much as it required up on the roof.
Remove all the tattered bits that have turned brown and shrivled up, also as hcmcdole mentioned, you can prune the flowering heads that have turned brow, you might not get a huge flush of new flowers this year BUT, it will remove a lot of the stress the plant has had trying to fight the heat, and the new leaves that are growing will offer a new start fore the plant,

dont prune end of season IF you do that now, BUT come early spring next year you can do a proper prune by removing any crossing branches so they dont run against each other, this rubbing allows infections & diseases to get hold, when you prune well, cut just above the new tint buds and cut the stems to about a foot tall, again removing any damaged ones, give a dressing of a slow chemical free feed, fish / bonemeal and blood is good and you hand fork it into the soil around the root area, this is a good slow releace fertiliser and just give the dosage recomended on the packet from garden store.

Hope this helps you out a little and good luck.
Kindest regards.
WeeNel.

thanks for the advice guys :) not sure where I can put it where it'll get light but not sun though...

Removing the plant from the roof terrace will be a big help, the actual flat roof is acting like a hot ring on a stove because it is holding onto the hot suns heating rays, IS there NOT an area of ground where that spot wont get hot sun all day, sun part of the day is better than baking it in an open cooker LOL.

Some hydrangeas like a lot of sun but the type you have does not appreciate the hot afternoon sun. Morning sun would be ideal or very late afternoon sun. Too much shade is not good either.

Can you erect some kind of umbrella/shade cloth over it? That would be the easiest thing to do. Perhaps put a small tub/pool under it to aid in humidity if your local humidity is low.

what type of hydrangea likes sun? maybe I'll invest in that species...

Paniculatas can take almost all day sun. Limelight, Phantom, Fire and Ice, Pee Gee (Paniculata Grandiflora), Vanilla Strawberry, Pinky Winky are some that I have. Try some of these full sun varieties.

It needs to be protected from sun, and need water, then it will be fine I hope.

thanks for the help everybody :)

good luck!