What to Do When Peony Leaves Turn Yellow
As a symbol of the nation's fragrance and elegance, yellowing leaves on peonies often worry enthusiasts. This article will systematically analyze the five key causes and provide actionable solutions to help you regain the magnificent grace of peonies.
Scientific Management of Water
Diagnosis of the Root Causes of Yellow Leaves
The fleshy characteristic of peony roots determines their fear of both waterlogging and drought. Data shows that 65% of yellowing leaf issues are caused by improper watering: waterlogging leads to root rot, while lack of water causes metabolic disorders.
Precise Irrigation Plan
Maintain a 7-day watering cycle in spring and autumn, and shorten it to 3-4 days in summer. Use the "dry-wet" principle, insert a bamboo stick to test soil moisture, and water thoroughly after the top 3cm layer dries.
Accurate Nutrient Supply
Warning of Imbalance in Fertilization
Yellowing leaves with green veins are typical symptoms of iron deficiency, while overall yellowing indicates a lack of nitrogen. Over-fertilization can easily cause the EC value to exceed the standard, leading to a "root burn" phenomenon.
Scientific Fertilization Timing
Apply nitrogen fertilizer (N-P-K=20-10-10) during the germination period, switch to phosphorus-potassium fertilizer (10-20-20) before flowering, and supplement with organic fertilizer after flowering. It is recommended to use slow-release fertilizer, with a dosage not exceeding 50g per square meter.
Optimization of Soil Environment
Adjustment of pH Value
The optimal pH value for peonies is between 6.2-6.8. When the soil becomes alkaline (pH>7.5), you can apply a ferrous sulfate solution (1:1000 ratio) monthly to adjust.
Soil Matrix Improvement Formula
Recommended proportion: garden soil 4 parts + decomposed leaf soil 3 parts + river sand 2 parts + bone meal 1 part. Conduct soil improvement every early spring, retaining 1/3 of the protective soil and replacing it with new matrix.
Comprehensive Control of Diseases and Pests
Identification of Common Pests
Spider mites (webbing on the back of leaves), aphids (honeydew on tender shoots), and root-knot nematodes (tumor-like structures on roots) are the three major causes of yellowing.
Green Control System
Physical control: Hang yellow sticky traps. Biological control: Release predatory mites (50-100 per plant). Chemical control: Alternate the use of abamectin (2000 times liquid) and pymetrozine (1500 times liquid).
By establishing a three-in-one maintenance system of "water and fertilizer control - soil improvement - disease and pest control," combined with regular observation and recording, the yellowing issue of peony leaves can be effectively controlled. It is recommended to create a maintenance log, recording the date, measures, and effects of each treatment, to form a personalized solution.