What are the reasons for the withering of gardenia leaves?
Today's life experience brings you the reasons for the withering of gardenia leaves and the related content about the causes of leaf withering and the solutions in the green plant aspect. The following is a detailed introduction.
The withering of leaves in potted gardenias is most commonly caused by chlorosis, with the main causes being excessive dryness of the soil, root problems, high alkalinity of the soil, and insufficient soil nutrients. It is necessary to pay great attention to the withering of gardenia leaves, first observing the growing environment and plant condition, determining the cause, and taking corresponding measures. Let's understand the reasons for the withering of leaves in potted gardenias and how to deal with them.
One, Excessive or Insufficient Soil Moisture
Gardenias need plenty of water, but the soil should not be overly moist, as this will cause the leaves to turn yellow, showing old leaves turning yellow and veins remaining green. While applying compound fertilizer to improve the growth matrix, move the potted plant to a ventilated area to dry, and water after loosening the soil, mastering the watering frequency. It is also essential to ensure that the pot has good drainage and the soil is breathable and ventilated. If the existing pot soil does not meet these conditions, consider repotting.
Two, Excessive Dryness of the Soil
It may also be due to the excessive dryness of the soil, especially in northern winters. The measure is to replace the pot with a larger tray, add water to the tray to let the potting soil absorb water, and place it on a north-facing window sill with scattered light until the plant recovers. If the old leaves turn from yellow to dry, the reason may be dry air, in which case it is necessary to increase the humidity of the air or spray around or place a damp towel on the ground.
Three, High Soil Alkalinity
If it is not caused by soil moisture, consider whether it might be due to high soil alkalinity. The best soil for growing potted gardenias is one that is breathable, loose, well-drained, and fertile. Gardenias prefer acidic soil, with a pH range of 5.0 to 6.5. If the soil pH is not suitable, the plant cannot effectively absorb the required soil chemical elements such as iron, nitrogen, magnesium, and zinc, leading to a deficiency of mineral elements such as magnesium and iron, which can cause chlorosis and yellowing of the leaves.
When magnesium is deficient, the leaf base and tip remain green, with the leaf base possibly turning dark green, and applying a certain dose of phosphates, such as a 1% magnesium sulfate solution, can help.
A lack of iron leaves the leaf base and veins green, and when the weather is cold, and the plant has difficulty absorbing soil nutrients, it can easily cause chlorosis. It is usually best to treat in spring, using a dilute solution of a sulfur-free agent to lower soil alkalinity, such as 0.2% ferrous sulfate solution.
Four, Poor Plant Adaptation
If the leaves of a plant in the acclimatization period first turn yellow and then develop burnt edges, move it to a position without direct sunlight to recover, ensuring that the soil moisture and air humidity are suitable. Avoid applying fertilizer and ferrous sulfate, and do not remove the yellow leaves.
Five, Insufficient or Improper Maintenance
1. Fertilization
A short-term solution for plant chlorosis is to directly supplement the deficient elements into the soil, but this is only temporarily effective. Long-term, it is necessary to fertilize regularly and in moderation. Apply fertilizer directly to the soil, away from the plant's roots, to reduce direct contact with fertilizer and avoid fertilizer burn, which is another way to reduce yellow leaves.
2. Temperature
The optimal growing temperature for gardenias is between 16 and 18 degrees Celsius, and they need a temperature of 5 to 10 degrees Celsius to overwinter. Below -10 degrees Celsius, they are easily damaged by frost, causing the leaves to turn yellow.
3. Light
Gardenias are sensitive to direct sunlight and should receive 60% full sunlight each day. An environment with insufficient light hinders photosynthesis.
4. Diseases and Pests
Plants with chlorosis and leaf spot disease will have leaves that turn yellow and gradually wither, while pests can also harm plant health, causing the leaves to become wilted and diseased leaves to turn yellow. Pests include刺蛾 (spiny caterpillars), scale insects, and whiteflies. It is essential to control diseases and pests promptly when discovered, and to take preventive measures and strengthen plant care to improve disease resistance.
The above sharing about the reasons for the withering of gardenia leaves and the detailed explanation of the causes and solutions for leaf withering are for reference and suggestion only!