As a new gardener I planted some new plants in an east facing raised bed folling the instructions and all of them began to thrive. About a month agao I noticed next doors cat peeing next to two of these - an acer shirasawanum ( approx 1 metre in height) and a pieris japonica katsura ( evergreen ) (50cm x 50cm). At the time I thought nothing of it as I didn't think cats harmed plants but now the internet tells me that they can. We have returned from our 2 week holiday and the little acer is now all brown shrivelled leaves and the pieris is drooping badly and has clumps of brown dead leaves on it. Are they gonners or will they come back. Could it be the cat, coincidence or the recent hot weather. Please help.