Native to tropical regions of Central America and the Caribbean, Philodendron hederaceum grows in warm, humid forests where roots stay lightly moist but still get air. That background explains why dense, soggy soil is a poor fit.
The best soil for Heartleaf philodendron is loose, organic-rich, and well-drained, with a loamy to peaty feel. Its roots prefer steady moisture around them, but they also need oxygen, so the substrate should hold some water without compacting. Slightly acidic to neutral conditions suit this balance well.