Troubleshooting
Thouars Cycad problems — and how to fix them
Thouars Cycad (Cycas thouarsii) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Crown and trunk rot
Standing water in the crown or poorly drained soil causes rapid Phytophthora or Fusarium rot; the central growing point collapses and fronds fall away. Remove all rotten tissue to healthy wood, dust with copper fungicide, and dramatically improve drainage.
Scale insects
Armoured scale (particularly cycad scale, Aulacaspis yasumatsui) encrusts leaflets and petioles, causing yellowing and dieback; scrub off with a soft brush and methylated spirits, then apply a systemic insecticide such as imidacloprid drenched into the soil.
Prevent thouars cycad problems before they start
Most thouars cycad issues are care-mismatch, not bad luck. Dial in the basics:
Thouars Cycad problems — FAQ
Why is my thouars cycad crown and trunk rot?
Standing water in the crown or poorly drained soil causes rapid Phytophthora or Fusarium rot; the central growing point collapses and fronds fall away. Remove all rotten tissue to healthy wood, dust with copper fungicide, and dramatically improve drainage.
Why is my thouars cycad scale insects?
Armoured scale (particularly cycad scale, Aulacaspis yasumatsui) encrusts leaflets and petioles, causing yellowing and dieback; scrub off with a soft brush and methylated spirits, then apply a systemic insecticide such as imidacloprid drenched into the soil.