How to Save Peony Leaves Turning Yellow
Peony is被誉为 the king of flowers, but yellowing leaves often occur during the maintenance process. Yellow leaves not only affect the ornamental value but also serve as a health warning signal from the plant. This article systematically analyzes the causes of yellow leaves in peonies and scientific treatment methods from four dimensions: water management, nutrient supply, root care, and pest and disease control.
Key Points of Water Regulation
Watering Quantity Standards
Experimental data shows that the soil moisture of potted peonies should be maintained between 40-60%. For small pots (diameter < 30cm), water 500ml every 3 days in spring and autumn, and for large pots (diameter ≥ 50cm), water 800-1000ml per week. Insert a bamboo stick into the soil for 2 minutes and observe; if the tip is moist, no additional water is needed.
Emergency Treatment for Waterlogging
In case of continuous rainy weather, immediately elevate the pot and tilt it at a 15° angle to accelerate drainage. In an emergency, wrap the pot wall with absorbent cotton cloth and use a fan at low speed to promote evaporation.
Scientific Fertilization System
Nutrient Element Ratio
Peony special fertilizer should contain a nitrogen-phosphorus-potassium ratio of 2:1:3, and calcium and magnesium fertilizers should be added during the germination period (50g per square meter). Organic fertilizers must be fully decomposed, sheep manure has a lasting effect of 90 days, and chicken manure needs to be diluted 10 times.
Remediation Plan for Fertilizer Damage
After excessive fertilization, immediately rinse with water 3 times consecutively, with 2-hour intervals. In severe cases, cut 1/3 of the leaves to reduce transpiration pressure and apply 0.1% gibberellin solution to the roots to promote new root growth.
Root Health Management
Potting Operation Specifications
The best potting period is September to October, retaining 1/3 of the protective soil. When pruning the roots, keep the main root length ≥15cm and apply charcoal powder to the wounds. The new soil should be mixed in the ratio of garden soil:rotten leaf soil:river sand = 5:3:2, with bone meal (100g/pot) as a base fertilizer.
Root Rot Warning Signals
Immediate root inspection is needed when the leaves have no dew in the morning, new leaves are curled more than 30°, and the potting soil has an odor greater than level 3 (by olfactory rating). Healthy roots should be milky white and have a diameter >0.3cm.
Three-Dimensional Pest and Disease Protection
Biological Control Technology
Release 500 aphid wasps per square meter to control aphids, and hang yellow sticky insect boards (20×25cm) to trap adult insects. In areas with high nematode incidence, plant pest-repelling plants such as marigolds, keeping a distance of 50cm.
Medication Use Standards
Apply 40% phoxim emulsion 1000 times solution to the roots to control grubs, and seal the film for 2 hours after application. Spray 70% methyl thiophanate 800 times solution at the beginning of leaf spot disease, focusing on the backs of the leaves.
By establishing a four-dimensional management system of water-nutrient-roots-disease, more than 95% of yellow leaf issues can be effectively prevented. It is recommended to conduct leaf SPAD value testing monthly, maintaining chlorophyll content >35μmol/m². Remember, prevention is better than treatment; regular observation of the plant's growth state is essential to keep the peony in its majestic and noble posture.