I have a Monstera, too...they thrive here in FL in sandy, loamy soil. A good tropical mix with compost but make sure it's well draining and there's air flow. That thing will climb to unbelievable heights if you let it.
Here's my tropical potting mix recipe:
1 part worm castings
1 part perlite
2 parts coconut coir
Handful bone meal tossed in
Handful Soil acidifier from Espoma
My potted tropicals do outstanding with this mix. My anthuriums haven't stopped flowering since I bought them 7-8 months ago. I even put shovel fulls of it in the hole when planting things in the ground.