So when do you get the zen garden?

[Teraku]

I've seen people talk about a "zen garden", I don't need to know what it is, I just want to know when you unlock it.

[bdmason]

Just keep playing through the story mode. I think it unlocks when the first potted plant gets dropped at the end of a battle. I'm not sure but I think it's in the 30-something levels.

[McMasterGold]

It is unlocked on level 5-4.