You can probably grow just about anything, but things with a long growing cycle, big root systems, heavy plants prone to falling over if not well-anchored, etc.

You can probably grow just about anything, but things with a long growing cycle, big root systems, heavy plants prone to falling over if not well-anchored, etc., are more work. So, fruit trees are a challenge, for example. They end up needing pretty involved scaffolding; I'd imagine that would be a particular challenge to implement with a robot.