What's eating my philodendron mexicanum?

Philodendron mexicanum, a long-lobed climber from Mexico and Central America, is vulnerable to the standard indoor aroid pests: spider mites, mealybugs, and scale. Mealybugs most commonly colonize the long petioles and stem nodes. Regular inspection at every watering, good humidity, and prompt isolation of any affected plant are key controls.

White cottony deposits along long petioles, stem nodes, and in the axil where leaves attach; sticky residue; stunted new growth Swab with isopropyl alcohol; spray with neem oil or insecticidal soap; repeat every 10 days for 3 rounds

Pale yellow speckling on the elongated lobed leaves; fine webbing on undersides; leaves may bronze and curl under in dry air Increase humidity; spray all leaf surfaces with neem oil; repeat weekly until no mites or webbing remain

Small brown or tan shells firmly attached to stems; leaf yellowing; sooty mold on leaves below infested stems Physically remove with a soft toothbrush; apply horticultural oil spray; recheck and treat monthly