Scale is another common pest that can cause a nuisance with your plant collection. In their lifetime of twelve weeks, they can lay up to three hundred eggs, causing a large infestation in a matter of months. Most larvae will only take five weeks to be able to reproduce.


Unlike Mealybugs and Spider Mites, this pest won’t produce a web to protect their eggs and instead will leave sticky patches from their excretions. In some cases, these areas will become black and remain sticky, caused by a fungus called ‘Sooty Mould’. Although this is mostly harmless to the plant, a thin film of fungi will reduce the plant’s ability to photosynthesise, thus weakening its health over time.

The individual Scale is a small, armour-shaped critter that’ll stay local to the hatching ground for many months. Depending on the species of Scale, the appearance may be brown, orange or even white, measuring around 0.4cm when matured. The critters will attach themselves to the foliage, stem and/or body of the cactus or succulent.


  • Firstly, scan your plant from head to toe. Take a few minutes to check all sides of the cactus or succulent, including its spines, body, leaves and stem. (Scale can be either brown or white, and should stick out like a sore-thumb when inspected closely).
  • For prickly cacti, it’s best to use an old toothbrush to brush off any critters and their eggs gently. If you can, use your fingernail to scrape them off, this is best as you can feel how hard you need to press. Remember always to be careful when using a toothbrush, as puncturing its skin and causing permanent damage is a risk. With your fingernails, gently remove the bugs. Smaller larvae may bury themselves in tight nooks within the plant, so it’s essential to scan the WHOLE plant from the soil line upwards. Use a warm damp cloth to wipe away areas that have the sticky substance or sooty mould.
  • Gently hose the foliage down under a tap to remove any remaining critters or the plant outside and gently hose the entire plant - its stem, leaves and any potential hiding spot. This is a critical part of addressing an infestation.
  • Situate the plant in a warm, bright room away from other specimens to dry-off. If the temperature is above 15℃ (59℉) at night, keep it outside to recover naturally. 
  • You can administer a pesticide once the foliage thoroughly dries. We recommend using SB Plant Invigorator Spray
  • Keep the affected plant away from others in a quarantined room until the symptoms have subsided for at least six weeks. In some cases, dormant eggs may hatch several months after deeming the specimen pest-free, so it’s always important to keep an eye out for a potential relapse. Keep other, non-affected specimens safe by distancing the pest ridden plant at least a metre away.