I just use portals to different areas of the map so I'll have one called "Farm" that has a boar enclosure + carrot / beet farm with some nearby tree plantings.

It's right next to the boss trophy power up area which I tried to use as a deer enclosure but made the mistake of allowing a tamed boar inside which went on a deer killing rampage. Yes you can't tame deer so it was just purely for fun and I eventually got to like 5 or 6 in the enclosed area.