What is wrong with my Pieris shrubs? I planted them late spring/early summer this year along with 2 rhododendrons.

Watered 3-4x a week (per the instructions from nursery) with miracle grow liquid feed and still watering

They are on the north side of my house (morning/noon sun)

They are dying, and I'm not sure why. The rhododendrons are doing fine with only a few brown tips on the leaves on the under carriage, but otherwise have had great growth. The pieris hasn't seemed to grow at all. Too much sun? Should i get some beach umbrella's until the summer is over?