Disease and Pest Control of Cereus flowers
As a highly ornamental succulent plant, Cereus flowers are favored for their brilliant blooms. However, many growers encounter issues such as abnormal plant growth without flowering and stem and leaf diseases. This article will systematically analyze common problems and scientific solutions from two dimensions: physiological diseases and pest control.
Analysis of Physiological Diseases in Cereus
Causes of Non-Flowering Excessive Growth
When Cereus flowers have lush stems and leaves but no flower buds, three key factors need to be investigated: insufficient light intensity limiting photosynthesis; excessive nitrogen fertilizer causing excessive vegetative growth; and unbalanced water management leading to abnormal nutrient transport. It is recommended to ensure 4-6 hours of scattered light daily, switch to phosphorus-potassium fertilizer during the bud differentiation stage, and maintain the substrate moist but not wet.
Management Plan for Yellowing of Abnormal Stems
Wilting and yellowing spots on the stem segments are often caused by direct sunlight. Full sunlight care is possible in spring and autumn, while in summer, it should be moved to a north-facing balcony or use a shading net. Yellowed stem segments can be cut off with a disinfected knife, and the cut surfaces can be coated with wood ash to prevent infection.
Key Points for Seasonal Maintenance
Add bone meal as a base fertilizer when repotting in spring, and apply磷酸二氢钾 foliar fertilizer in autumn. Maintain an environment above 10℃ in winter, reducing watering frequency to once a month. Keep the environment well-ventilated throughout the year, and periodically loosen the surface soil with bamboo sticks to enhance aeration.
Common Pest Control of Cereus
Identification and Treatment of Disease Types
Initial symptoms of stem rot include brown water-stained spots, which can be treated with carbendazim solution; brown spot disease is characterized by reddish-brown spots on the leaves, and it is recommended to remove the diseased leaves and spray with mancozeb; root knot nematodes cause tumor-like swellings in the roots, requiring soil replacement and disinfection with abamectin.
Golden Period for Pest Control
Spider mites are prevalent in dry seasons, with weekly spraying on the back of leaves for prevention; scale insects often hatch in spring and autumn, and can be physically removed with alcohol swabs; during the爆发 period of aphids in May-June, hang yellow sticky traps for monitoring in advance.
Biological Control Alternative Solutions
Introduce ladybugs to control aphids, and release predatory mites to control spider mites. Homemade chili water (200g fresh chili + 1L water soaked for 24 hours) can repel soft-bodied pests, environmentally friendly and residue-free.
By combining scientific diagnosis with preventive maintenance, the disease resistance of Cereus flowers can be significantly improved. It is recommended to establish a maintenance log, recording watering and fertilizing times, occurrence of diseases and pests, and gradually mastering the growth patterns of the plants. Regularly check the back of leaves and stem joints with a magnifying glass for early detection and treatment.