Euphorbia lactea 'Cristata' Discoloration: Graft Quirks and Watering

The coral cactus (Euphorbia lactea cristata) is a graft of two species. Dark, spreading spots that don’t rub off are often genetic disorders, not pests or disease.

Care Checklist

• Pot size (4″) and cactus mix with perlite are correct.
• Water every 2–3 weeks if in full sun on an uncovered windowsill.
• Ensure pots have drainage holes; use distilled water if tap is hard.

Reality Check

These novelty grafts are inherently unstable. If corrected watering doesn’t help, the discoloration is likely genetic and untreatable.