Reasons and Solutions for Blackened, Withered Edges on Gardenia Leaves
Gardenia is a fragrant, light-loving ornamental flowering plant with many varieties, including large shrubs and small shrubs suitable for container growing. Regardless of the type, problems are very likely to appear after planting, especially in containers where growing space is limited and poor growth is common. Sometimes blackened leaves and even withered edges are also commonly seen, and the cause is unknown, so today we will mainly explain what to do about this situation.
1. Disease occurrence
The main cause of blackened plant leaves is sooty mold, which can infect many plants, and gardenia is no exception; after infection, the leaves become covered with a layer of black material. It may also be gardenia anthracnose, where brown spots appear on infected leaves, gradually drying out and turning black, and after small black dots form, a small patch turns black. Use Bordeaux mixture protectant preventively in advance; when disease occurs, drench the roots with a 40-fold ferrous sulfate solution, then spray the leaves with 0.2% ferrous sulfate.
2. Pest damage
Some piercing-sucking pests feed on leaf sap, after which the leaves turn yellow and black and then dry up and fall off, so to deal with these piercing-sucking pests, the best approach is to remove larvae as soon as they are found, collect them in a container, and kill them with pesticide; apply pesticide to diseased branches, and in severe cases cut off the diseased branches and spray pesticide.
3. High temperature and drought
If the temperature is very high and the weather is unusually dry, the leaves will lose water and gradually dry up, usually starting from the leaf edges; during drought, the roots in the soil also cannot absorb water, the plant becomes dehydrated, and this shows first on the leaves. When high temperature and drought occur together, sometimes spiders gradually die of dryness. If grown in a container, it can be moved indoors and watered; if grown in the open ground, water in the evening and keep watering consistently.
4. Excessive humidity
Generally, too much watering, or heavy rain, or continuous overcast and rainy weather, will all cause excessive humidity; soil moisture cannot be released, and the humidity of the entire environment is very high. Water accumulates, the roots are prone to becoming waterlogged and rotting, after which nutrients cannot be absorbed, and infection by pathogens is likely; after this happens, the leaves turn black and dry up. Water according to the situation, and drain during the rainy season.
When the gardenia's growing environment changes and becomes unsuitable, it will show on the leaves; blackening, drying up and the like are all like this. Therefore, pay attention to improving the environment and adjusting growth in time; if pests and diseases occur, focus on prevention and control, and the situation will improve.