Many gardeners include hibiscus plants in their flower gardens. Their beautiful, colorful flowers brighten up the space. Then, you discover yellow leaves on hibiscus plants, and you worry that you killed your plant on accident. There is no need to fret; yellow leaves on these plants are typical. However, they are a call for help, so measures must be taken.
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Why Do the Leaves Turn Yellow?

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Before you address the problem, let’s learn about why the leaves turn yellow. Hibiscus leaves turn yellow, and often drop off of the plant, because of stress. The hardest part is determining the cause of the stress. There are a few common reasons for stress in a hibiscus plant. Your goal is to figure out the issue; then you can relieve it. Then, your leaves should go back to normal.
8 Common Forms of Stress in a Hibiscus Plant
1. Too Much Water
If the weather is cold or cloudy, too much water could be the problem. Hibiscus plants like to be moist, but not drenched with water. When the sun isn’t beating down, and it is cooler, an abundance of water leads to the stress of the root system. During dormancy, you need to decrease watering. You should water just enough to stop the soil from completely drying. Containers should have proper drainage.
2. Too Little Water
A different issue could be at work. If it is warm outside, you should be giving plenty of water to your hibiscus plants. Typically, you should water them every day or every other day. Many gardeners love a watering system on a timer to ensure their plants get the proper amount of water. Other use self-watering pots to avoid their plants becoming stressed. Remember, if it is hot outside, keep your plant well watered.

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3. Too Hot or Too Cold
The weather can lead to stress on your hibiscus plants. Ultimately, the weather does lead down to water as well. On those scorching, summer days, your plant is more stressed and needs an abundance of water to keep those huge leaves green.
Temperatures above 90 degrees can lead to stress. When they don’t have enough, they turn the leaves yellow, so they don’t require enough water.
Likewise, weather that is too cold can lead to problems. Remember, hibiscus plants are a tropical plant. They don’t handle freezing temperatures, below 38 degrees F, very well. They excel in temperatures 65-85 degrees F. When a hibiscus plant is too cold, they will turn their leaves yellow.
4. Sunlight
All plants need the proper amount of sunlight. Hibiscus plants do love sunlight, but they require moderate amounts. If you place your plant in an area that receives all day sun, their leaves will turn yellow or develop white spots. You can think of the white spots like a sunburn. Don’t worry; they won’t die because of the white spots, and it doesn’t indicate death.
Sunlight is the life source for all plants. If they don’t receive enough sunlight, they will drop some of their leaves, leaving less to support. It is your job to place the hibiscus plants in an area that receives a few hours of uninterrupted sunlight each day but still get shade.
It also could be a sign that your plant is ready to go dormant. Since they are tropical plants, winter is when they typically go dormant. If the yellow leaves coincide with the normal dormancy, allow the plan to enter its stage naturally. Bring it inside for the winter. When you bring your plant indoors, you can expect a moderate amount of yellow leaves. If all the leaves are off but the branches are pliable, it is in full dormancy.
5. Annoying Insects
Certain insects, especially spider mites, cause problems for hibiscus plants. If you notice the mottling of the leaves, it is time to check for spider mites. The leaves will look dirty and tired, with marks on the underside. Slowly, the leaves will turn yellow and fall off. Spider mites can destroy every leaf on your plant, so you need to treat them! It takes a few weeks for your plant to recover.

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6. Improper Nutrition
If the yellow leaves on hibiscus aren’t completely yellow or falling off, there is a chance your plants have Chlorosis, which is caused by improper nutrition. You may need to apply fertilizer or check the pH level of the soil. Your soil should be on the acidic side. The problem is relatively easy to fix. You either need to amend the ground or provide more nutrients to the plant. Remember, if the leaves aren’t bright yellow and remain on the plant, chlorosis could be your problem.
7. Soil
As mentioned above, the pH level of your soil may be wrong. Soil compaction could also be a problem. Probe the ground around the plant and lift it out of the pot. If the roots are packed or circling, you need to repot your plant. It is best to use a light, well-draining potting mix. Hibiscus plants prefer to be just a bit crowded, so don’t opt for a huge pot.
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8. Pesticide
Most gardeners don’t apply pesticide to their hibiscus plants. However, if you do, it could be the cause of the stress. Overuse, using the wrong type, too strong or using at the wrong time of day all could lead to yellow leaves. If the yellow leaves occur soon after the application of a pesticide, it is likely to be a stressor for your plant.

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Now What?
Now that you know the common forms of stress, you can fix the issue. Addressing the stressor is the only way to stop the yellow leaves on hibiscus plants. Typically, yellow leaves won’t kill your plant, but the stressor could cause death. For example, if your plant requires more water and never receives any, you could end up losing your plant. An infestation of spider mites left alone will eat away your entire hibiscus plant. If you notice those yellow leaves, they are a call for attention. Don’t ignore them if you want to keep your plant!