What's eating my zebra plant (calathea zebrina)?

Zebra Plant Calathea is especially vulnerable to spider mites — the velvety green-and-dark-striped leaves show stippling damage early. Mealybugs and scale also colonise the undersides and stems. High humidity deters mites significantly; inspect weekly, particularly in winter when central heating dries indoor air.

Tiny pale spots and webbing on leaf undersides; velvety texture becomes dull and leaves may yellow at edges. Raise humidity with a humidifier or pebble tray; spray with neem oil or insecticidal soap weekly for a month.

White cottony deposits at leaf bases and in the crown; sticky residue on pots and nearby surfaces. Isolate the plant, wipe with alcohol swabs, and treat repeatedly with neem oil spray until no signs remain.

Brown or tan bumps fixed on stems and midribs; leaves yellow and the plant loses vigour over time. Scrape off individual scales with a soft toothbrush or cloth; follow up with horticultural oil or neem oil spray.