Possums are tricky.
Different possums in different places eat different things. Some people will grow potatoes without problems, others will get all of theirs eaten by possums. Sometimes possums will leave something alone for a while, and then they'll eat it.
One year I planted buckwheat and the possums were really interested in eating that, and ignored my other plants while there was still buckwheat left, so planting stuff that they prefer might be a good strategy, although it also might encourage them.
Mustard greens grew fine here early in the season, but now a possum has decided to eat the one plant I had left.
Zucchinis were fine, possums like to eat pumpkins/winter squash though.
Possums or
rabbits ate all of my beans, but one bean plant that was hiding in some borage plants got ignored - I wonder if hiding the plants in amongst stuff they don't eat is a good idea?
The possums here ignore tomato plants until the tomatoes are ripe, and then they eat the tomatoes themselves but not the plants.
Wallabies will eat the entire vegetable garden, but are safer around fruit
trees than possums.
Nettle was growing on a part of my
land, where there is a lot of wildlife, so that might be ok. Nettle where I am seems to just grow in spring, and then it disappears until the next spring. If there was a
enough of it, it could be dried and used all through the year though.
A strategy might be to plant stinky plants that deter them near your edible plantings, and that will hopefully keep them away. I considered a border of wormwood all around my garden, but it's allopathic so I don't want that to be too close to my plants.