Growli

Pest identification

What's eating my column cactus?

Scale insects

Signs: Flat brown bumps adhered to ribs; sticky honeydew leads to black sooty mold patches.

Control: Remove mechanically with a brush and alcohol. Spray neem oil or horticultural oil over the whole column; repeat after 14 days.

Mealybugs

Signs: Fluffy white deposits in rib grooves or at the apex; feeding weakens new growth.

Control: Dab colonies with isopropyl alcohol; follow with a neem oil spray. Repeat every 7–10 days and isolate the plant.

Spider mites

Signs: Fine silvery stippling on the column surface; may see minimal webbing under magnification.

Control: Improve humidity, wipe the stem with a damp cloth, and apply neem oil or miticide spray every 5–7 days.

Keep column cactus pest-free

Healthy plants resist pests best. Get the basics right:

Column Cactus pests — FAQ

What is eating my column cactus?

Column Cactus (Cereus validus) is a robust houseplant with few serious pest problems, but mealybugs and scale insects can colonize its rib grooves. Spider mites are a risk in heated, dry rooms. The plant's thick skin limits damage, but honeydew from scale can attract sooty mold. Inspect ribs monthly and act at first sight.

How do I get rid of scale insects on column cactus?

Flat brown bumps adhered to ribs; sticky honeydew leads to black sooty mold patches. Remove mechanically with a brush and alcohol. Spray neem oil or horticultural oil over the whole column; repeat after 14 days.

How do I get rid of mealybugs on column cactus?

Fluffy white deposits in rib grooves or at the apex; feeding weakens new growth. Dab colonies with isopropyl alcohol; follow with a neem oil spray. Repeat every 7–10 days and isolate the plant.

How do I get rid of spider mites on column cactus?

Fine silvery stippling on the column surface; may see minimal webbing under magnification. Improve humidity, wipe the stem with a damp cloth, and apply neem oil or miticide spray every 5–7 days.