Can you get those pvc green house things? either put potted plants on the shelves as is, or for larger areas just buy the covers to fit over the area you need to cover. Maybe not the prettiest solution, but easy and inexpensive. My semp baths are against our flat wall, we have quite a wide troughing area (don't know what its called lol) so they will be sheltered to a small extent, I don't know if it'll make much of a difference. If not I did think about putting stakes into the corners of the baths and attatching a piece of corrigated persspex as a bit of a shelter. But I'll wait and see how much pour our autumn rain affects my semps first.
