The Reasons and Solutions for Dianthus Yellow Leaves
Dianthus, as a common ornamental flower, the issue of yellow leaves has been troubling many horticulture enthusiasts. Yellowing leaves not only affect the ornamental value but may also indicate impaired plant health. This article will visually present typical symptoms through three sets of comparative images, systematically analyze the causes, and provide practical solutions.
Diagnostic Guide for Three Major Causes of Dianthus Yellow Leaves
Light Imbalance Causes Metabolic Disorders
Indoor cultivation often leads to insufficient light, causing older leaves to yellow first and new leaves to become malformed. Long-term lack of light can trigger edema disease, with transparent watermark spots on the back of the leaves. Suggestions: Ensure 4 hours of direct sunlight daily, with a south-facing windowsill and supplementary lights for better results. After removing yellow leaves, apply chelated full-element fertilizer to promote photosynthetic pigment synthesis.
Improper Water Management Damages Roots
Frequent watering can cause root rot, resulting in uniform yellowing of young leaves in a chlorotic state; drought stress, on the other hand, manifests as curling and withering of older leaves. Improved solution: Use the "lifting pot" method to determine moisture, water thoroughly when the pot is 1/3 lighter. For plants with waterlogging, remove the pot, prune blackened roots, soak in carbendazim, and then repot with new soil containing 30% perlite.
High Temperature Stress and Nutrient Deficiency
Temperatures above 32°C in summer can trigger a dormancy mechanism, causing yellowing of new leaves with interveinal chlorosis. Suggestions: Shade 50% at noon and maintain ventilation, spray EDTA-Fe chelated iron (1000 times solution) on the leaf surface, and apply pH 6.0 ferrous citrate solution to the roots, once a week for 3 weeks.
Advanced Maintenance Techniques
Preventive management includes: supplementing decomposed sheep manure every month during spring and autumn, using red clay pots to enhance breathability, and regularly rotating the pot to ensure even light exposure. Isolate yellow leaves immediately to prevent disease spread.
By adjusting light, precise watering, temperature control, and supplementing trace elements, the yellowing phenomenon can be effectively reversed. It is recommended to conduct soil EC value testing every quarter, maintaining the substrate conductivity within the range of 1.2-1.8 mS/cm to create the best growth environment for Dianthus.