Help - hydrangea damage. Why? (Photos)

[NonHerbalReasoning]

A week or 2 ago my hydrangeas were healthy, lots of spring growth. Last few days the top leaves have turned brown or yellow, and wilted.

We had a cold snap (-4) a few days ago, plus I'm not sure if they're under watered or over watered!

How can I figure out if I ought to water them?

I would expect soft spring growth exposed to temperatures of -4 to suffer frost damage. I doubt it's anything to do with watering. The burnt bits will go crispy and be replaced with new growth in due course. As long as the soil is damp they will cope (unless freshly planted in which case they will need more water till established).

Yes, that sounds right. They are starting to dry up a little. Thank you!

Mine has done the same thing ! Looked great last weekend. Now it's brown around the edges.

Frost damage, mine are the same. The warm weather encouraged new growth, soft tender shoots and leaves, sharp frost kills them.
Hopefully they will regrow...keep an eye on them and the weather reports, if a frost is forecast cover the new shoots with a layer of newspaper or even better horticultural fleece from b&q or the garden centre.

My hydrangea bed has got the frost this week - I am gutted as we protected the stuff in the greenhouse, but I forgot about my pride and joy which is a massive bed full of hydrangeas which I added to, year on year.

Should I remove the crispy bits?