I would think it looks more like over-fertilizing or weedkilling rather than something else. Did you or someone applied anything in the area this spring or previously? I've never seen anything so bad, so may be trying flush the residue with water may help. It is not a question of how nice it will look this year or next but rather about survival of the plant. I see a couple of bottles? Did you spray it with something? Or may be it is too close to the footpath and there is salt involved?