I planted new hydrangeas last week and watered them very well. I left for a 5 day vacation with the understanding my neighbor was going to water my plants for me. I got home today and my baby hydrangeas look SO burnt! I'm assuming my neighbor forgot about watering for me.. I am so sad because I really was excited for them. It's been very hot this weekend so I'm sure it's something to do with sub damage and being dehydrated.

What can I do to save them?! I am VERY new to gardening so any advice will help as I am still learning! I have attached pictures of the flowers. Please note: for some reason they look MUCH better in the photos.. but I felt they would still be helpful.

It looks like the flowers are toast but they will be back next year. Worry about the plants themselves. From what I can see, they look pretty good, some burnt edges but overall, good.

Plants that small should not have been allowed to bloom in the first place. When a plant has flowers, they put all their energy and efforts into producing seed so the next generation will survive. These may be Hydrangeas that don't produce seeds but, in the plants mind, seeds are the all important end to this story.

Cut the flowers off and keep them well watered. Don't blame your neighbor, especially if you haven't spoken to him. Those plants were stressed from the beginning. Newly planted in hot weather and trying to support flowers. Way too much to ask of your new plants and your neighbor.

Also adding, if your neighbor watered them when the sun was out that could have been the cause of them burning up, I've always been told to water early in the day so that water doesn't sit on the plants to dry in the hot sun. How thick is the layer of mulch around them, could it be not enough water got down to the roots?

:welcome:
Looks like sun scorch. Did you acclimate them to their new growing location? More than likely they had been grown in a greenhouse and needed to slowly be introduced to the new sun conditions.
No worries, the plants will survive.

Christine said:Also adding, if your neighbor watered them when the sun was out that could have been the cause of them burning up, I've always been told to water early in the day so that water doesn't sit on the plants to dry in the hot sun. How thick is the layer of mulch around them, could it be not enough water got down to the roots?

Watering pots well before planting is also important for the reason Christine said in the last sentence. If the rootball is too dry when they are planted it is almost impossible to re-wet it enough by watering the bed.

Just to add, there was a scientific study a while back on watering in the sun and it found that unless a plant has very hairy leaves, the sun doesn't burn wet leaves. If it did, then all plant leaves would burn every time the sun came out following rain.

The reason for watering early in the day is indeed so that they] leaves dry more quickly but that's to avoid encouraging fungal diseases, most of which need a period of leaf wetness to cause an infection. That's why overhead watering at night or late evening is not a good idea, the leaves stay wet much longer in the more humid and dark night-time, perfect conditions for fungal diseases.