How to rid a six year old cactus of mold or fungus?

Question

I have a cactus (in house). The other day I looked and there was a white fuzzy substance on it. Looked like mold or fungus of some kind. I need to get rid of it before it smothers the cactus. I barley ever water it, I know it's not humidity causeing this. I'm not a green thumb so I'd like some advice on what I should do for it. The cactus is six years old so I sure would like to save his life.

Answer 1

It's not mold. It's either mealy bug or scale.

Mealy Bugs: white/gray insects about 0.1 inch (3mm) in length. Mealy bugs dine on cactus sap and reproduce rapidly laying their eggs underneath a cotton-like elliptical covering. This white covering also serves to protect the insect from predators and pesticides. A plant infested with mealy bugs is covered with these white spots and sticky honeydew. No parts are immune to their attack; while most often you will find them on the stem, we have also found them adhering to the spines of the plant. Left unchecked, infested plants will stop growing, take on a sickly-deformed appearance, and start to shrivel. Weakened plants often succumb to fungi and rot.

Minor mealy bug infestations can be handled by mechanically removing the pests (i.e. using fingernails, scrub brushes, tweezers, and/or water pressure). Dabbing the insects with a cotton swab previously dipped in rubbing alcohol is the preferred treatment. Alcohol dissolves the waxy coat and kills the bug.

Systemic or contact insecticides may also be used to control widespread mealy bug attacks. Malathion and dimethoate are often recommended. Before applying insecticides, insure that the plant has been well watered a day prior and always read and follow instructions carefully. Weekly re-applications are sometimes required for complete control.

Mealy bugs may also attack the roots of a cactus causing the plant to appear sickly. If you can't locate any insect above ground on sickly plants, root mealy bugs may be feasting on the plants roots. To eliminate, unpot the plant and rinse off all of the white spots and soil using warm water. Remove any suspicious looking roots and allow the plant to dry. After the plant has dried, repot into a fresh soil mixture.

To be absolutely safe, you may want to take cuttings from an infested plant, apply an insecticide to the cuttings and start off some new plants.


Scale: pinhead-size insects that present themselves as raised tan/brown or white spots. These spots, resembling marine limpets, are actually hard shell coverings that protect the insect or eggs underneath. Scales reproduce like rabbits, prefer columnar and rock cacti, and dine on plant juices. Infected plants appear yellow and weakened. Left untreated, scale can cause bud and shoot drop. Scale are treated similar to mealy bugs. Minor infestations may be remedied by washing the plant with a weak detergent solution or by mechanically removing insects with a toothpick. Malathion may be used to control major infestations. When fighting scale, be sure to cover the soil, otherwise, these pests will just drop off and then get right back on the plant.

Answer 2

Cactus Fungus

Answer 3

It is the residue of an insect, it will destroy the plant. I can't remember the name of the bug, but the best way to get rid of it and others on plants is to spray the plant daily with soapy water. It won't hurt the plant, but will kill the bug. If you rub the white substance it will turn red. It is a pretty good dye

Answer 4

loose the jacket and I say it's an adorable spring outit!! Also the earings might compete with the headband...less is more!! One more thing, the shoes look so formal with a casual look! But for a six year old its cute!! :)

Answer 5

check the roots for exposure or some sort of insects?yu could make a spray of dish soap and water and lightly spray it? will kill insects such as fruit flys,or aphids.if real bad infestation make a slurry of tobacco and water,it makes a insectcide too. also if yu have a cat..........? check that out too?