The Reasons and Solutions for Yellow Leaves of Phalaenopsis
As a high-end ornamental flower, the yellowing of Phalaenopsis leaves is a common problem in the maintenance process. This article systematically sorts out four typical causes and scientific solutions for the yellowing phenomenon of Phalaenopsis leaves, helping flower enthusiasts accurately diagnose the symptoms and restore the plant's jade-like luster.
One, Yellow Leaves Caused by Waterlogging and Root Rot
Cause Analysis
Phalaenopsis aerial roots are sensitive to humidity, and long-term immersion in waterlogged substrates can lead to hypoxia and root rot. Data shows that more than 70% of Phalaenopsis yellow leaf cases are related to improper watering.
Processing Steps
Urgently remove the pot, use a sterilized scissor to remove the black rot roots, and it is recommended to soak in a 0.1% potassium permanganate solution for 20 minutes. After drying the roots for 24 hours, replace with a mixture of pine bark and sphagnum moss (4:6), keeping the substrate slightly moist in the initial stage.
Two, Light Burn Type Yellow Spots
Symptom Identification
Leaf edges appear burnt yellow spots, mostly concentrated on the sunny side of the plant. Experiments show that Phalaenopsis can develop burns under 30000lux of light for more than 3 hours.
Environmental Control
Immediately move to an east-facing windowsill, equipped with a 40% shade rate curtain. Retain 1/3 of the healthy part of the yellowed leaves and apply plant ash to the cut to prevent infection.
Three, Nutritional Imbalance Yellowing
Deficient Element Manifestation
Overall yellow leaves accompanied by smaller new leaves, commonly seen in plants that have not been repotted for a long time. When the nitrogen, phosphorus, and potassium ratio is unbalanced, the tip of the old leaves first appears yellow.
Scientific Fertilization
Add slow-release fertilizer granules (N-P-K=20-20-20) when repotting, apply diluted Florduo No.1 at 2000 times every half month during the growing season, and stop fertilizing in winter.
Four, Temperature Stress Yellow Leaves
Physiological Disorder
Low temperatures in winter (＜15℃) cause leaf discoloration, and high temperatures in summer (＞32℃) trigger metabolic disorders. Temperature sudden changes cause net-like yellow spots between veins.
Temperature Control Plan
Equip with a thermometer and hygrometer, maintain day temperature at 25-28℃/night temperature at 18-20℃. Use a heating pad in winter and a mini circulating fan to cool down in summer.
Through systematic diagnosis and precise intervention, more than 90% of Phalaenopsis yellow leaf problems can be improved within 2-3 weeks. It is recommended to conduct leaf镜检 monthly during daily maintenance, use an EC pen to monitor substrate salt content, and sprayBrassica napus extract to enhance stress resistance, keeping your Phalaenopsis in the best condition all year round.