Troubleshooting
Zamia Palm problems — and how to fix them
Zamia Palm (Macrozamia riedlei) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Phosphorus toxicity
As a native of phosphorus-impoverished soils, this species is unusually sensitive to phosphate fertilisers. Excess phosphorus causes leaf burn, yellowing, and can be fatal. Always use phosphorus-free or very low-phosphorus fertilisers.
Root rot in heavy soils
Any compaction or waterlogging, even briefly, can initiate caudex rot. Plant in raised beds with deep gravel drainage, or in unglazed terracotta containers with extra-gritty mix. Do not mulch heavily over the caudex crown.
Cycad scale (Aulacaspis yasumatsui)
This invasive armoured scale can rapidly defoliate cycads. Inspect all frond surfaces and the caudex regularly. Treat with repeated horticultural oil applications every 2 weeks and apply systemic imidacloprid as a soil drench for severe infestations.
Prevent zamia palm problems before they start
Most zamia palm issues are care-mismatch, not bad luck. Dial in the basics:
Looking for zamia palm in general rather than its problems? Read the full zamia palm care guide — light, water, soil and feeding.
Zamia Palm problems — FAQ
Why is my zamia palm phosphorus toxicity?
As a native of phosphorus-impoverished soils, this species is unusually sensitive to phosphate fertilisers. Excess phosphorus causes leaf burn, yellowing, and can be fatal. Always use phosphorus-free or very low-phosphorus fertilisers.
Why is my zamia palm root rot in heavy soils?
Any compaction or waterlogging, even briefly, can initiate caudex rot. Plant in raised beds with deep gravel drainage, or in unglazed terracotta containers with extra-gritty mix. Do not mulch heavily over the caudex crown.
Why is my zamia palm cycad scale (aulacaspis yasumatsui)?
This invasive armoured scale can rapidly defoliate cycads. Inspect all frond surfaces and the caudex regularly. Treat with repeated horticultural oil applications every 2 weeks and apply systemic imidacloprid as a soil drench for severe infestations.