Your Calathea will never thrive in regular potting soil, and here's why. Standard mixes retain too much moisture and don't provide the aeration these plants desperately need. In nature, Calatheas grow in Mexican Nopales Salad (Cactus Salad) Echinopsis Schick hybrid 'Don Juan' buds, 2 inch pot size eBay Cactus Park in Barcelona (Jardins de Mossn Costa i Llobera) Bonhams : Mitch Epstein (born 1952); 'Oak Bluffs, Martha's Vineyard, Massachusetts' (from 'Recreation II');