Orchid cacti (Epiphyllum spp.) are epiphytic plants that thrive in well-draining, aerated substrates. Root rot occurs when the roots are exposed to excessive moisture, leading to fungal or bacterial infections. From the plant's perspective, root rot disrupts nutrient and water uptake, causing systemic stress and eventual decline if untreated.
2.1 Discolored Roots: Healthy roots are firm and white or light tan. Rotting roots appear dark brown or black, mushy, and may emit a foul odor.
2.2 Yellowing or Wilting Leaves: As roots fail to function, the plant cannot absorb water or nutrients, leading to chlorosis (yellowing) and limp, drooping stems.
2.3 Stunted Growth: The plant may stop producing new shoots or flowers due to energy diversion toward surviving the infection.
2.4 Leaf Drop: Severe cases trigger premature shedding of stems or leaves to conserve resources.
3.1 Overwatering: Orchid cacti store water in their stems and prefer drying out between waterings. Constant dampness suffocates roots.
3.2 Poor Drainage: Heavy or compacted soil retains water, creating anaerobic conditions ideal for pathogens like Pythium or Phytophthora.
3.3 Contaminated Tools or Soil: Reusing infected pots or unsterilized tools spreads pathogens to healthy roots.
4.1 Optimal Watering Practices: Water only when the top 1-2 inches of soil are dry. Reduce frequency in cooler months.
4.2 Well-Draining Soil Mix: Use a blend of orchid bark, perlite, and coarse sand to mimic their natural epiphytic habitat.
4.3 Proper Pot Selection: Choose pots with drainage holes and avoid oversized containers to prevent waterlogging.
4.4 Sterilization: Disinfect pots and tools with a 10% bleach solution before reuse.
4.5 Environmental Control: Ensure bright, indirect light and good air circulation to keep foliage and soil surface dry.
5.1 Root Inspection: Gently remove the plant and trim affected roots with sterile scissors until only healthy tissue remains.
5.2 Repotting: Transplant into fresh, dry soil and withhold water for 1-2 weeks to allow roots to heal.
5.3 Fungicide Application: Treat remaining roots with a copper-based fungicide to prevent reinfection.
