Why Does Euphorbia Obesa Lose Its Leaves
As a tropical plant with high ornamental value, the issue of Euphorbia obesa leaves dropping困扰s many gardening enthusiasts. This cactus species is favored for its unique shape, but when leaves start to fall abnormally, it often indicates potential dangers in the growing environment. This article will systematically analyze four common causes and provide targeted solutions.
I. Imbalance in Temperature Control
1.1 Symptoms of Low Temperature Injury
When the ambient temperature continuously drops below 7℃, plant cell activity sharply decreases, leading to brown frostbite spots on the leaf edges, followed by the shedding of leaves in large numbers. Especially in northern regions, the temperature changes around the winter heating period often become hidden killers.
1.2 Precise Temperature Control Solution
It is recommended to move the plant to a sunny indoor area before the first frost and use double-layer thermal insulation film to create a mini greenhouse. At night, a warm air blower can be used to maintain a constant temperature of 15-20℃, ensuring a safe distance of over 50cm to prevent burns.
II. Optimization of Soil Structure
2.1 Diagnosis of Compacted Soil
When the surface soil cracks and the water渗透 speed exceeds 30 seconds after watering, it indicates that the soil is severely compacted. Long-term lack of oxygen in the roots can lead to the decline of absorption function,表现为 lower leaves dropping first.
2.2 Key Points of Potting Operation
Repot every year around the Spring Equinox, using a mixture of ceramsite + decomposed leaf soil + coarse river sand (2:3:1) as the growing medium. During the operation, retain 1/3 of the protective soil, trim the aging roots, and soak in carbendazim for 20 minutes before planting.
III. Water Management Techniques
3.1 Warning Signs of Waterlogging
When water continues to seep from the bottom of the pot for over 2 minutes, or the soil below 3cm remains moist, it indicates excessive watering. Long-term waterlogging can cause root rot, initially manifested by yellowing of new leaves, followed by shedding of old leaves.
3.2 Scientific Watering Solution
Use the "Bamboo Stick Test": Insert a roasted bamboo stick into the potting soil and check the moisture after 15 minutes. Maintain a watering cycle of 7 days in spring and autumn, shorten it to 5 days in summer, and extend it to 15 days in winter.
IV. Fertilizer Application Standards
4.1 Typical Symptoms of Fertilizer Burn
When the leaf tips show burnt spots and white salt crystals precipitate on the pot wall, it indicates the risk of fertilizer burn. The ammonia released by uncomposted organic fertilizer can directly damage the stomatal structure.
4.2 Safe Fertilizing Strategy
Apply a balanced liquid fertilizer diluted 2000 times monthly during the growing season, combined with a microbial fertilizer every quarter. During the winter fertilizing break, spray a foliar fertilizer of potassium dihydrogen phosphate (0.2% concentration) to maintain nutrition.
By systematically adjusting temperature, improving the substrate, precision watering, and scientific fertilizing, the issue of Euphorbia obesa leaves dropping can be effectively solved. It is recommended that caregivers establish observation logs to record environmental parameters and plant changes, gradually mastering the growth patterns. Practice shows that continuous scientific care for 3 months can achieve a leaf regeneration rate of over 85%.