Mealybugs
How to tell
White, cottony fluff tucked into leaf joints and along stems, sometimes with sticky residue.
The fix
Dab each one with a cotton swab dipped in rubbing alcohol, then treat with neem oil. Check weekly: they hide.
Most likely cause
Spider mites. Rinse the plant in the shower, wipe the leaves, raise humidity, and treat with insecticidal soap or neem oil weekly until clear. Isolate it from other plants.
What’s causing it
Scale
How to tell
Small, brown, limpet-like bumps stuck to stems and the undersides of leaves, often with sticky honeydew.
The fix
Scrape them off gently with a fingernail or old toothbrush, then treat with neem oil and keep checking.
Fungal leaf spot
How to tell
Brown or black spots, often with a yellow halo, usually after the leaves were wet or the soil was overwatered.
The fix
Remove affected leaves, improve airflow, avoid getting water on the foliage, and let the soil dry more between waterings.
Sunburn (not a pest)
How to tell
Dry, bleached, or brown dry patches only where strong direct sun hits the leaf, with no bugs or webbing. Purple heart wants bright light and some direct sun.
The fix
Shade it from the harshest midday sun for a few weeks, then let it back into the bright spot gradually.
Prevention
Inspect new plants before bringing them home, check the undersides of leaves now and then, keep humidity up to deter mites, and isolate anything infested.
More for your Purple heart
All Purple heart guides
Related plants
Same genus or the same care pattern.
Last reviewed: 2026-08-19