More than likely, the water is missing the original root ball. Stick a finger into to it to check.

Yes, the root ball is moist (just checked it this morning). When it started browning out we began soaking the base of the plant.

With the extreme sun and heat we've had in the NW this month, I would think it's probably just the wrong time to be planting anything, especially a shrub that doesn't do so well in heat and sun. I'd pull the survivors up, put them back in the pots and into the deep shade somewhere, keeping them well watered until the weather cools and the rains return. Then replant them.

You were a little late watering the plants. "When they started to brown out", is the clue. By then, the damage was done.
If you keep them watered they should be OK. Just don't let them dry out again.
Mike

Consider rigging temporary shade because I'm told this heat will continue.

If needed, replacement plants put in next spring will quickly catch up to the others.

It's hot!
Temporary shade is a good idea, jean.
I've been out on the Olympic Peninsula for the last three days and came today back to wilting established hydrangeas that I don't normally water. I'll take a look at them in the morning and see how they are doing. They're a long ways from a hose bib.
Mike

Doin' fine.
'Weiderspink'
Mike

Beach umbrellas work well. I bought several at a Big Lots on the cheap (5 bucks each!) to help along some hostas that had been in the shade but now get a lot of sun due to a limbed up tree. Worked out pretty well and they look cute :)