Beginner Gardening: unhappy roof terrace plants, 1 by photosynthesize

photosynthesize wrote:
Hello... I know almost nothing about plants and I am humbly asking you experts for some support. I put some plants on my roof terrace in the summer and they were generally doing OK, but as winter has progressed some have died completely and others seem to be halfway there. I\'d really appreciate any help you could give me - I think the hydrangea and the one I don\'t know the name of (pic 1) are being chomped on by something... and the wisteria and little conifer thing and the rosemary have maybe gone a bit dried up despite the constant rain...? I do have some miraclegro stuff (blue powder that you dissolve in water) but as they\'ve all been so drenched lately I didn\'t want to deluge them further by giving them that too.