Why do gardenia leaves turn black and dry up?
“Gardenia flowers bloom, so beautiful so white, this is the season, we will leave” - everyone is familiar with this campus song by He Jiong, and the impression of gardenia flowers in it is especially deep. Gardenia flowers are pure and elegant; although they lack the brilliance of peonies or the delicate charm of roses, they have a unique refined appeal. Gardenia flowers generally appear in the wild, and nowadays many people grow them in pots at home; not only are they beautiful, but during the flowering season the whole room carries a faint fresh fragrance. Recently a friend asked, why do gardenia leaves turn black and dry up? Let us explore this together.
1. Improper watering
Gardenia flowers should not be watered too frequently; generally you should wait until the soil surface begins to dry before watering, otherwise water will accumulate, and gradually the roots will slowly rot because they cannot breathe. The whole gardenia plant then has no nutrients, and this gradually shows on the leaves, which begin to turn yellow, dry up, and even turn black and drop off.
At this point we should water according to the specific condition of the gardenia, neither too much nor too little. If the root rot described above occurs, the rotten parts need to be cut off and then the plant replanted. In summer, the amount of watering can be appropriately increased; while keeping the soil moist, you can spray water on the leaves to cool them down, but do not use too much at one time.
2. Caused by pests
If gardenia flowers are infested by pests, this can also cause the leaves to turn black and dry up. Because many people do not know what its main pests are, they do not prevent them well or treat them in time, and so this situation occurs.
Generally speaking, the common pests of gardenia flowers include aphids, whiteflies, scale insects, and so on. The main thing is to treat the specific problem, keep the leaves clean, and after handling, place the plant in a cool, ventilated place and then observe how the leaves recover.
3. Lack of potassium, iron, and magnesium
When gardenia leaves turn black and dry up for no apparent reason, or even the whole plant dies, it is very likely due to a lack of potassium, iron, and magnesium; the specific deficiency should be identified according to the leaf color.
1. If potassium fertilizer is lacking, it generally first shows from the leaf edges and then moves toward the center; old leaves will change from green to brown. If this situation is not controlled in time, it will affect the survival of the whole gardenia plant, so nitrogen fertilizer should be supplemented.
2. If iron and magnesium are lacking, chlorosis will first appear on the leaves; new leaves become lighter in color or turn white, while the leaf veins remain green, and finally the leaves dry up and die. If this is the case, timely spraying of ferrous sulfate aqueous solution and boron-magnesium fertilizer should be used for prevention and control.
4. Unsuitable temperature
The most suitable growing temperature for gardenia flowers is 16-18°C. If the temperature is too low, it will enter a dormant state; if the temperature is too high, it will scorch the roots or leaves, causing the leaves to turn black and die. Especially in the hot summer, proper care is essential: generally move it outdoors in the morning and evening, move it indoors at noon, and spray water in time to cool it down.
5. Excessive light
Gardenia flowers are plants that prefer partial shade. If exposed to strong sun in summer, the leaves are easily scorched, causing them to die. Therefore, appropriate shading is needed to avoid direct sunlight. In winter, when there is sunshine, move it to a balcony to sun for 4-5 hours.
Summary: If gardenia leaves turn black and dry up, check whether it is caused by the above five major reasons. Discover it early and solve it early; by all means do not wait until the whole plant dies before trying to save it, because even if the cause is found, there is still a high chance it will die.