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Roots
Root Mealybugs on Cacti
Commonly affects: Cactaceae (Cactus)
The plant declines gradually with no obvious above-ground pest signs, and when unpotted, small white cottony masses are visible on the roots themselves.
Potential Causes
- 1Root mealybugs feeding on root tissue below the soil surface, often going unnoticed until decline is advanced
- 2Introduction via contaminated soil or an already-infested plant
- 3Dry potting conditions that root mealybugs actually tolerate well, unlike some other pests
Solution Steps
- 1Remove the plant from its pot and rinse roots thoroughly to physically remove visible mealybugs
- 2Discard the old potting soil entirely rather than reusing it
- 3Repot into fresh, sterile cactus mix
- 4Consider a systemic insecticide drench for persistent, hard-to-eliminate infestations
Prevention Tip
Since root mealybugs hide below the soil, unexplained decline in an otherwise well-cared-for cactus warrants checking the roots directly rather than assuming a watering issue.
