Mulch it heavily and water, water, water.
Your new RAISED bed may have a too good drainage to retain enough moisture this plant is definitely need at this time of the year.

Mine have been in the ground 2 years now and do the same thing. My soil is basically beach sand. Last year I bought some small metal stakes and I think some plastic weed block material and made 3 x 3 foot shaded areas for them. Also mulched heavy this year.

Large leaf plants suffer from wilting during any summer. Newly planted hydrangeas do this often on their first summer (or maybe two) so keep an eye on them. After they are established, wilting will occur on windy days or unusually hot days.

Ignore the wilting episode if the plant recovers on its own by next morning. If it does not, increase the amount of water you have been giving it for the duration of summer (but remember to go back to normal in the fall). If you notice extreme wilting, water immediately; otherwise, water when the soil feels dry, or almost dry, to a depth of 4".

People with sandy soils -like Alan- will need to always water more than someone with good soil, probably in the order of 30-50%. People with clay soil will need to water less than someone with good soil. Adding organic ammendments like compost will help greatly in sandy (or clay) soil. And, of course, no matter what your soil is like, always add 3-4" of mulch through or past the drip line. That was not a typo: four inches.

Feel free to break some of the suggestions/rules on a plant that is not established (Good luck with those new babies,
Luis

Luis_pr : you are a Hydrangea genius! I am having the same problem, with the wilting and burning of my plant, which I moved from the back of the house due to ZERO sun, and lots of leaves but not blooms. I have several back there, and I started with one last fall. I gets morning/early day sun, but not more than 2 hours, so I was surprised about the burning. The leaves are very light green, which I know is not right. I got one pale pink bloom, and I think it's a lace cap since it was rather flat, not a big ball, but it could just be the fact that its the first year. I was pleasantly surprised to get the bloom I got. My questions:1) will it adjust to the sun it's getting next year? 2) when I move the others (4 of the same type and a few babies that grew beneath the Oak leaf that's growing in back (albeit just one bloom), what kind of sun can they handle? I have room right next to the wilty one, and also around the corner in the front, which gets probably at least 4 hrs of late afternoon sun. I was worried its too much sun for hydrangeas, but not enough for Lilacs - what I really want to plant there. Let me know your thoughts about sun, and maturing hydrangeas. I am going out to water it right now! Thanks.