Scale Insects on Aloe Vera — Identification and Treatment
Aloe Vera (Aloe vera)
Symptoms
- small brown or tan bumps on leaf surfaces
- bumps that don't brush off easily
- sticky or shiny residue on leaves
- yellowing or pale sections beneath scale clusters
- ants on plant attracted to honeydew
Causes
Scale insect infestation
Scale insects (Coccidae and Diaspididae families) are sessile insects that settle onto plant tissue and cover themselves with a hard waxy shell — which is what makes them look like small bumps and what makes them so difficult to kill with contact insecticides. They feed by inserting a stylet (feeding tube) through the plant's surface and extracting phloem sap. On Aloe vera, they typically appear on the flat leaf surfaces and along the serrated edges. Soft scale species produce honeydew; armored scale don't.
How to Fix It
- 1
Confirm scale before treating: press a fingernail under the edge of one bump. An insect body coming away underneath means scale; a bump that stays fused to the leaf is just natural surface texture, common on thicker Aloe leaves.
- 2
For small infestations: scrape off scale manually with a soft toothbrush or plastic card; then wipe the affected areas with 70% isopropyl alcohol.
- 3
Apply horticultural oil spray (neem oil or insecticidal oil) to all affected surfaces. The oil suffocates scale insects that the physical removal missed.
- 4
Set a reminder to repeat the alcohol wipe and oil spray on a 10–14 day cycle for about 6 weeks total. The dead female's shell shields her egg mass from the first couple of treatments, so it's the newly hatched crawlers you're catching on each follow-up round, before they settle and grow their own shells.
- 5
For severe infestations on multiple leaves: consider treating with a systemic insecticide (imidacloprid as a soil drench) if physical and topical treatments are insufficient.
Prevention
- Inspect new plants before introducing to collection
- Check Aloe leaves during monthly care checks — scale is most visible in bright light
- Maintain good air circulation
Quick Summary
| Plant | Aloe Vera (Aloe vera) |
|---|---|
| Category | Pests |
| Likely causes | Scale insect infestation |
| Fix steps | 5 steps — see above |