Earth Garden... an interesting concept.
No, the Luna cry hit the desert continent Centra!
Well, the previous Lunar Cry destroyed Centra. And why? Because the Crystal Pillar was there. We know, from Laguna's sequence, that the Lunatic Pandora was definitely in Trabia, at least for a time - probably when Esthar was messing around with it. I reckon that crater is where it was stored or hidden while they were figuring it out.

Of course, the crater is there to impede progress above all else, but it's still interesting to contemplate the 'real' reason for it being there.