Every year I plant seeds. Every year the possums eat the first green leaves. I replant and replant apparently for their pleasure and I get nothing. This year, they left one lonely cucumber vine. Woo hoo, 3 cukes so far!!!
I put tomato cages over stuff I want to protect and then wrap chicken wire around the bottom of it and make sure it’s all touching the ground all the way around.
You could also plant some very aromatic herbs to confuse them with their scent. The benefits are reduced pest pressure, less weeding (because if the herbs aren’t there the weeds will be, and you can harvest the herbs for your own use.