There are many possibilities of conflict between cats and plants (read Keep Cats Out of Your Garden for a few examples), but main one that I went through was between Nounouche, my aging tomcat, and my plant lights.
In general, Nounouche was the perfect cat for a gardener: he never chewed on my plants or played with their foliage, nor did he ever mistake a pot for a litter box. However, he did like to sleep under the gentle heat produced by my fluorescent lights. He’d settle down there every morning, pushing my plants out of his way if that were possible. If not, he’d simply lie on them. Let’s say I was not very happy with the results!
I tried to install a chicken-wire barrier around my lights, but not only did that make maintenance more complicated, he soon managed to find a way through the barrier. And the idea of surrounding the space with prickly plants turned out to be disastrous: he simply pushed the spiny greenery right off the shelf and onto the floor!
We ended up making peace though … when I gave in to him! I learned that if I left him a space free of plants under one of the warmest lights, he’d always settle there. No exceptions. I ended up simply giving him a plant tray all of his own and it instantly became his bed. No more damage!
Nounouche is no longer with us, alas (although he lived a long life: 16 years!) and Geisha, his replacement, has never shown the slightest interest in my light garden, nor in my plants in any way. (Lucky me!) But if a future kitty does start eyeing my plant lights, I now know exactly what to do!