Troubleshooting
Coryphantha macromeris problems — and how to fix them
Coryphantha macromeris (Coryphantha macromeris) 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.
Rot of the soft tubercles
The long, fleshy tubercles rot easily if kept cold and wet or in a peaty mix. Use a mineral substrate and keep dry through winter.
Floppy, stretched tubercles
Too little light makes the tubercles soft, pale and lax and stops flowering. Move to full sun for firm, compact growth and summer blooms.
Overwatering swelling and splitting
Heavy watering after a dry spell can swell and split the tubercles. Water evenly and let the mix dry fully between soakings.
Mealybugs and scale
Pests shelter at the base of the crowded tubercles and on the roots. Inspect at repotting and treat with alcohol spot-treatment or a systemic insecticide.
Prevent coryphantha macromeris problems before they start
Most coryphantha macromeris issues are care-mismatch, not bad luck. Dial in the basics:
Looking for coryphantha macromeris in general rather than its problems? Read the full coryphantha macromeris care guide — light, water, soil and feeding.
Coryphantha macromeris problems — FAQ
Why is my coryphantha macromeris rot of the soft tubercles?
The long, fleshy tubercles rot easily if kept cold and wet or in a peaty mix. Use a mineral substrate and keep dry through winter.
Why is my coryphantha macromeris floppy, stretched tubercles?
Too little light makes the tubercles soft, pale and lax and stops flowering. Move to full sun for firm, compact growth and summer blooms.
Why is my coryphantha macromeris overwatering swelling and splitting?
Heavy watering after a dry spell can swell and split the tubercles. Water evenly and let the mix dry fully between soakings.
Why is my coryphantha macromeris mealybugs and scale?
Pests shelter at the base of the crowded tubercles and on the roots. Inspect at repotting and treat with alcohol spot-treatment or a systemic insecticide.