Why Are My Hibiscus Leaves Turning Yellow? Plant Experts Explain

Hardy hibiscus plants are a landscaping staple, brightening up gardens with their giant blooms. But as with many plants, there are certain conditions you need to help your hibiscus plant thrive. We spoke to some experts to explain why hibiscus leaves turn yellow—and how to turn the situation around.

How to Care for Hibiscus Plants

Hibiscus plants have colorful flowers that can grow as large as 12 inches in diameter. Their robust, trumpet-like blooms come in various hues, including pink, red, peach, orange, yellow, purple, and white. Though hibiscus is best known for growing in tropical and subtropical climates, with the proper care, it can also do well in temperate climates.

Care and growing requirements are species-specific, so familiarize yourself with the type you have before planting. The flowers bloom in the summer and fall and need lots of sunlight, moist soil, and fertilizer.

To keep your plant in peak condition, prune it during the spring to allow room for the blooms to stretch out. Water your hibiscus plant regularly, and spread mulch around the base to help seal the moisture into the soil. Temperature requirements depend on the species, but hibiscus plants generally love humidity.

Common Causes of Yellow Hibiscus Leaves

Before you start playing plant detective, understand that having some yellowing hibiscus leaves—especially on old growth—is totally normal. "Before the older leaves fall, the plant sends a ‘retirement signal’ to the leaf, and the plant stops the production of chlorophyll in that leaf, pulling any remaining collected energy back into the plant," says plant expert Jennifer Foster. However, if you're getting a lot of yellowing on new growth, there may be an underlying issue you need to fix.

Over- Or Under-Watering Your Hibiscus Plant

Too much or too little water is the most common reason why your hibiscus leaves may be turning yellow. "If the soil is staying soggy, then this can cause the roots to rot," says design director Cate Singleton.  "But hibiscus plants need a good deal of water. If the soil gets too dry, this can cause stress to the plant."

Changes to the Plant’s Environment

Any changes to your hibiscus plant's environment—such as more shade, less humidity, or cooling temperatures—could cause the plant's leaves to yellow. "Changes can cause the plant to drop some leaves in order to adjust to the new environment," Foster says.

Lack of Sunlight

Hibiscus plants are tropical, which means they need plenty of sunlight to grow. They do best in direct sunlight or partial shade. "In most parts of the country, hibiscus plants require full sun to thrive—so if your plant isn't getting that, it may drop some leaves," Singleton says.

Nutrient Deficiencies

Haven't fertilized your hibiscus plants in a while? A lack of nutrients—particularly phosphorus and nitrogen—can be to blame, Foster says. Hibiscus plants that don't receive enough nutrients can develop a condition called iron chlorosis, which causes the leaves to turn yellow.

Insect Infestation

Pests like spider mites, aphids, and mealybugs can all be potential culprits if your hibiscus has yellowing leaves. "Their feeding habits can cause yellowing of leaves," Foster says. "Check the undersides of leaves as well as the spaces where leaves and branches intersect, all of which are good places for insects to hide."

How to Solve Yellowing Hibiscus Leaves

Fortunately, for each problem, there's a solution that helps stop the yellowing of leaves. Try these tactics to help your hibiscus plant thrive.

Water Your Hibiscus Plant Properly

Your hibiscus should be in well-draining soil, and get water every few days for optimal growth. "If your plant is soggy, try adding compost to the soil to correct it, while mulching the plant (and of course, watering more) can help if a lack of water is to blame," Singleton says.

Keep Your Plant in an Appropriate Environment

"If you will be moving the plants between indoor and outdoor locations, make sure you acclimate the plant slowly between each location to reduce stress on the plant," Foster says.

"Hibiscus plants thrive in more humid conditions, with humidity levels around 50 percent," Foster says. If you live in a hot and dry climate, you can help create that by placing your hibiscus near other plants or a water feature.

Get Your Hibiscus More Sun

If your hibiscus plant is in a shady area, moving it to a sunnier spot in your garden or home will help it thrive. Hibiscuses do better the more sunlight they have, so be sure that you're only allowing partial shade.

Strengthen Your Soil

If your soil nutrients aren't meeting your plant's needs, adding a fertilizer with equal parts nitrogen, phosphorus, and potassium can help your hibiscus plant to thrive, Singleton says. This can be especially important if your plant is potted. "Plants kept in containers need regular applications of fertilizer to keep them happy and healthy," Foster says.

Address the Insect Issue

Aphids, mealybugs, and spider mites all respond well to some simple interventions. "Pests can generally be controlled with a good water spray to the leaves," Singleton says. "If this doesn’t clear up pest problems, an insecticidal soap can also help."