Troubleshooting
Square-stemmed Pelargonium problems — and how to fix them
Square-stemmed Pelargonium (Pelargonium tetragonum) 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.
Stem rot from overwatering
The most frequent cause of failure; the jointed semi-succulent stems rot rapidly in wet compost, especially in cool conditions. Water only when compost is bone-dry and reduce dramatically in winter.
Etiolation in low light
In insufficient light the stems lose their characteristic square cross-section and become thin, weak, and pale green. Move to a sunnier position; the plant needs direct sun for at least 4-5 hours daily.
Prevent square-stemmed pelargonium problems before they start
Most square-stemmed pelargonium issues are care-mismatch, not bad luck. Dial in the basics:
Square-stemmed Pelargonium problems — FAQ
Why is my square-stemmed pelargonium stem rot from overwatering?
The most frequent cause of failure; the jointed semi-succulent stems rot rapidly in wet compost, especially in cool conditions. Water only when compost is bone-dry and reduce dramatically in winter.
Why is my square-stemmed pelargonium etiolation in low light?
In insufficient light the stems lose their characteristic square cross-section and become thin, weak, and pale green. Move to a sunnier position; the plant needs direct sun for at least 4-5 hours daily.