Ask-a-Dave's-Gardener: snowball hydrangeas dying, 1 by Lemisate48

Lemisate48 wrote:
hi! newbie to DG so if i’m posting improperly pls forgive! we have 8 snowball hydrangeas that were planted on our wooded lot last summer in August. idiotically, we didn’t figure deer grazing, awful soil (clay and rock), and an incredibly hot and dry then monsoon-like wet summer into the equation. they are in partial shade, have been chewed repeatedly (tho my husband swears he is spraying deer repellant every now and again ...) and now are looking generally scraggly with some small spent blooms, leaves are turning brown then black on some and others are turning brown/black at tips of stems where deer chewed off new shoots. one has lost all leaves except 2 and all its stems are brown. is there any way to save it and the others as fall approaches? i’m so sad. we live in southeastern PA on edge of the poconos.