Scale Insects

About this condition

Infestation by scale insects that attach to stems and leaves to feed on plant sap. Left unaddressed, they can trigger sooty mold and significantly weaken the plant.

Common symptoms

Small white, cream, or brown shell-like bumps attach to stems and leaf bases
A sooty black residue may appear on leaf surfaces
Overall plant growth slows and new shoots fail to develop
Leaves may yellow or shrivel in affected areas

Common causes

Long-term management in poorly ventilated or dry indoor conditions
Introduction of infested plants or new stock from outside
Pests spreading between plants in overcrowded growing spaces
Proliferation in indoor settings with few natural predators

Prevention (growing conditions & routine care)

Quarantine newly purchased plants for a period to check for pests. Inspect plants regularly and maintain good air circulation. Avoid overcrowding by spacing plants adequately.

When to see a vet

Consider acting within a few days

What can a nursery or grower do?

Specialist nurseries can help identify the type of scale insect, assess infestation severity, advise on physical removal methods, and recommend improvements to ventilation and placement. They can also check for secondary issues such as sooty mold.

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