Potted plant leaves looking bad? Diagnose easily with pictures
Temperature
Too high
Symptoms: In flowers that prefer cool conditions, the tips and edges of young leaves scorch and dry, and the leaves may even drop off.
Measures: Move them promptly to a ventilated, shady spot.
Too low
Symptoms: When winter room temperatures are low, flowers that like high temperatures develop yellowing leaves.
Measures: You can slip a plastic bag over the plant to keep it warm, and place it somewhere out of cold drafts.
Light
Insufficient
Symptoms: Stems are slender, internodes are longer, leaves are thin and weak with paler color, and the whole plant shows leggy, spindly growth.
Measures: Increase the time of sunlight exposure or move the light source closer.
Too much
Symptoms: The plant's leaves curl and have yellow edges, and new leaves do not grow large.
Measures: Shade appropriately or move the light source farther away.
Sunburn
Symptoms: Yellow-brown spots appear on the leaves, and leaf edges and tips scorch, curl, and shrivel.
Measures: Spray water promptly to cool the plant and raise humidity, shade appropriately, and prevent direct sunlight.
Watering
Insufficient
Symptoms: Leaves shrivel and droop, and the plant's leaves turn yellow and drop from the bottom upward.
Measures: Spray water on the leaves promptly, then water lightly to let the plant recover slowly. Usually water appropriately according to the plant's habits.
Too much
Symptoms: The plant's young leaves turn yellow first, then the old leaves also yellow; some wilt and drop, or even die.
Measures: Loosen the potting soil and place the plant in a ventilated spot to speed up water evaporation. Water by the principle of dry-then-wet, watering thoroughly each time, and often check whether the drainage holes at the bottom of the pot are blocked.
Humidity
Insufficient
Symptoms: Leaves curl and wrinkle and turn yellow-brown.
Measures: Besides spraying water on the leaves more often, you should also sprinkle more water on the ground around the potted flowers.
Too high
Symptoms: Leaves turn yellow, curl, and wither.
Measures: Move the flowerpot to a dry, ventilated spot to lower the humidity.
Fertilizing
Insufficient
Symptoms: New leaves and stems do not grow, branches and leaves are thin and weak, and leaves are yellow and thin.
Measures: Promptly apply dilute, well-rotted fertilizer or compound flower fertilizer, or simply repot into fresh, loose, fertile potting soil.
Excessive
Symptoms: White crystals appear on the surface of the potting soil and along the rim of the pot, and the plant's leaves shrivel, rot, and drop.
Measures: First water to dissolve the white crystals; after half an hour, water heavily to flush out the overly concentrated fertilizer salts (if nothing is wrong in winter, just don't fertilize).
Too much nitrogen fertilizer
Symptoms: The plant forms few flower buds, does not bloom, and only grows leggy stems and leaves.
Measures: Reduce nitrogen fertilizer application; especially during bud formation, avoid nitrogen fertilizer and apply more phosphorus and potassium fertilizer.
Pests and diseases
Diseases
Symptoms: Leaf spot disease easily causes localized leaf necrosis, with yellow spots or patches appearing; in severe cases the whole leaf withers, yellows, and drops. After infection by mosaic virus, yellow-green mottling appears on the leaves.
Measures: For potted tree-type plants, you can spray the protective agent "Hushu Jiangjun" in winter and early spring to sterilize by suffocation and kill overwintering pest eggs.
Pests
Symptoms: When attacked by scale insects, red spider mites, and other pests, the leaves also become locally yellow and withered, or even the whole leaf yellows and drops.
Measures: Use vinegar (rice vinegar); dip a small cotton ball in the vinegar until wet, then gently wipe the affected stems and leaves of the flowers and trees with the wet cotton ball.
Pot too small
Symptoms
The pot is packed with exposed fibrous roots, and roots also poke out through the drainage holes at the bottom. After watering, the leaves tend to wilt, and new leaves are few and small.
Measures
Repot immediately into a larger flowerpot.
How well have you all learned your "medical skills"? Are you ready to go out into the world?