PLEASE help with customers Indian Hawthorn bushes

[nlowplacez]

I'm trying to help the sweetest old lady in the world, as I may have messed up her hedges. She told me she wanted them trimmed down to her bottom window sill, so I took off like 6 inches to a foot from the top of the hedges, which seemed like way too much, and I still wasn't close to the window sill. The hedges were now barren and not fully lush and green with a lot of visible branches and whatnot. But we both thought after a while the leaves will come in and fill her back out. Now a week or two later the leaves on top are browning and it doesnt seem to be filling in. I read before i did this that the Ind. hawthorns were super strong and pretty much resistant to anything, so i didn't imagine i could have a problem like this . is there anything I can do to revitalize the hedges, or am going to be paying for a reinstall. thanks in advance, and PLEASE help

[BCLawns]

give it some more time and make sure they are getting enough water (not too much)

[Az Gardener]

Drape some shade cloth over them to prevent sunburn on exposed branches. Some extra water would probably also help. When you see some new buds swelling fertilize them lightly.

[Southern Elegance]

superthrieve works wonders