What's eating my pitaya agria?

Pitaya Agria (Stenocereus griseus) grown as a houseplant faces mealybugs as its primary pest, clustering in the deep ribs and areoles. Scale insects and spider mites follow in dry heated rooms. Routinely inspect the rib valleys where pests escape notice until populations are well established.

Cottony white deposits in rib grooves and areoles; distorted or stunted new growth; sticky honeydew attracting sooty mould Treat each colony with isopropyl alcohol on a cotton swab; spray the whole plant with neem oil solution every 10 days for a month

Firm brown shell-like spots on ribs; sap-drained areas appear sunken or discoloured over time Scrub off with a soft toothbrush; apply horticultural oil or neem oil spray and repeat after 14 days

Fine webbing and a dusty greyish tinge to the epidermis; most common in winter when indoor heating reduces humidity Rinse the cactus with water to knock off mites; apply insecticidal soap spray; boost humidity around plant slightly and ensure good airflow