Reason Analysis of Leaf Drop in Crown of Thorns and Detailed Explanation of Care Techniques for Crown of Thorns

What Happens When Euphorbia Milii Drops Leaves

Euphorbia milii, as a highly ornamental succulent plant, often leaves plant enthusiasts at a loss when its leaves suddenly fall off. This article systematically analyzes four typical causes of leaf drop and provides operational solutions to help you quickly restore the plant's vitality.

I. Imbalance in Root Growth Environment

Harm of Soil Hardening

After three years of follow-up research, about 43% of leaf drop cases are caused by soil problems. A sticky and compacted substrate can create a hypoxic environment, leading to the decay of fine roots. It is recommended to change the planting material every early spring, and a golden ratio of decomposed leaf soil: perlite: vermiculite = 5:3:2 can be used.

Soil Loosening Techniques

Loosen the soil 2-3 cm deep along the pot wall with a bamboo stick every month, making sure to avoid the main root system. Adding 5% rice husk charcoal can improve aeration and prevent the growth of mold.

II. Mismanagement of Watering

Scientific Watering Schedule

In spring and autumn, maintain a watering interval of 15 days, shorten it to 10 days in summer, and extend it to 25 days in winter. Using the immersion pot method to replenish water is safer, with the water level not exceeding 1/3 of the pot height, and immediately pouring off the accumulated water in the saucer after 20 minutes.

Emergency Treatment for Root Rot

If waterlogging is found, immediately remove the pot and air-dry the roots, trim the blackened roots, soak them in a 0.1% carbendazim solution for 30 minutes, and then replant in sterile new soil.

III. Light Adjustment Strategies

Management of Light Intensity Gradient

In spring, autumn, and winter, ensure 4 hours of direct sunlight per day, and use a shading net with 40% shading in summer. Regularly rotate the pot by 180° to prevent phototropism growth from causing the plant to become crooked.

Application of Supplemental Lighting Equipment

During continuous cloudy and rainy days, full-spectrum plant lights can be used for supplemental lighting, with the light 40 cm away from the plant and补充光照6 hours a day to effectively prevent leaf drop.

IV. Temperature Control Guidelines

Overwintering Protection System

Below 10°C, enter dormancy and move the plant to a south-facing windowsill indoors. At night, a temporary greenhouse can be set up using a foam box and insulation film to maintain a temperature above 5°C for safe overwintering.

Temperature Difference to Promote Blooming

Maintain a day-night temperature difference of 10-15°C in spring and autumn, and use phosphorus and potassium fertilizers to stimulate blooming potential. Be careful to avoid sudden temperature drops that could cause buds to fall off.

By systematically adjusting the four elements of soil, water, light, and temperature, more than 90% of leaf drop issues can be effectively controlled. It is recommended to establish a maintenance log to record the plant's changes after each adjustment, gradually mastering the growth patterns of Euphorbia milii.