I would also look into Rootmaker pots. They are amazing for developing a proper root system and have products for stepping up pot size from seedling to full grown tree.
See: https://rootmaker.com/rootmaker-system
12 years ago I started 60 seedlings using their RootMaker Express 18 tray system (3” pots, 18 per tray), and potted up every two years thereafter.
Check them out; you will not be disappointed.