Are these well and truly dead?

[Peonii]

I've recently put some flowers and plants in my garden and had been trying to follow all textbook advice diligently. I am not a gardener and not good at it either. I had to go away unexpectedly to look after my dad for just over a week. Anyway, I've come back and this is what my hydrangea plant looks like. I've watered them A LOT just now. Is it salvageable? 😭

They're pretty wrinkled but you have hopefully caught them in time. Hydrangeas like plenty of water, so now that you've watered them, leave it until tonight when it cools down then water them again, let the ground get really soaked.

Are they in full sun? If so, and you need to go away again for a time, then give them a really good watering/soaking just before you go.

Give them a good soaking and leave them for a week. The flowers may die back (in which case, cut them off) but the plants should survive.

If the flowers do die back DO NOT cut them off, just leave them on the bush. I know it looks unsightly, but Hydrangea flowerheads should not be cut off the bush now - rather wait until next April/May after any risk of frost, THEN cut the heads off.
If you cut them off now, it won't flower next year.

Two years ago when we had that 40 C temp weather, my Hydrangea almost caught fire - I found it smouldering! All the flowers died, but I left them on until the following spring and now it's back better than ever.

Hydrangea flowerheads look lovely in winter when they are covered in frost. As a pp says, leave them on, because they also offer frost protection to the plant beneath.

They are really thirsty plants, which reminds me - I need to go and water mine this afternoon.

Ah thank you so much everyone. Fingers crossed. I love their bluey colour and was feeling so sad they might have been gone forever.

If the flowers die, does anyone know if I can expect any more to pop up this year? Just curious now.

No, they only have one flowering per year. But, as unsightly as it would be leaving dead flower heads on the bush throughout Winter they will, as a pp said, protect the stems from frost - which is why you do not remove the heads until the risk of frost is past around May time.

I trimmed the heads of mine too early one year as I thought all the frosty nights had finished - but no! All the leaves developed frost burn and turned brown. Very few flowers that year too.

Here's hoping you're blooms have recovered. Please do let us know how it goes.

Progress photos now that they are Slightly more hydrated

Hydrangeas flower once a year, so when those flower heads are finished, you will have to wait until next year before it flowers again.

The clue is in the name! 'Hydra' means water! They need lots of water