I have a snow world with a little bit of forest and plains all of the map. No joke like 85% of the map is snow. I was wondering if I put down a patch of sand randomly on the map will cactus spawn on the sand? If I cant do this is it posible for cactus to spawn randomly on the map after I have fully rendered all of the chunks on the whole map?
No, the cactus will not randomly spawned after the world has been generated.
Sorry bud.