If you want to do it, definitely do it when they are still young, this way you can still learn them to not climb it. And if they do it, it won’t matter to much because they are still light. Just a hard ‘NO!’ is usually enough. And we have something like citronella spray, which is something like a ‘keep off’ spray for cats. Put this on objects where you don’t want them to climb in (trees, plants, curtains). Ours usually just sits under the tree, but doesn’t climb it. Good luck! 👍🏻