Stepping into your garden one day, you may spot the telltale signs of distress on a tropical hibiscus: yellow leaves standing out against the vibrant flowers. A few yellow leaves are a normal part of the plant’s natural renewal process. But when many leaves turn yellow or the plant looks unhealthy, it’s time to investigate.
Keep reading to learn why hibiscus leaves turn yellow and what to do about it.
What Are Hibiscus Plants?
Hibiscus plants are stunning flowering shrubs known for their large, colorful, and trumpet-shaped blooms. They belong to the mallow family (Malvaceae) and include hundreds of species, but most fall into two main categories:
- Tropical Hibiscus (Hibiscus rosa-sinensis): These are the varieties most commonly grown as houseplants or in warm climates. They produce showy flowers in a wide range of colors, including red, pink, orange, yellow, and white. Tropical hibiscus are evergreen and thrive in USDA hardiness zones 9-11.
- Hardy Hibiscus (Hibiscus moscheutos and others): These plants are native to parts of North America and can handle colder temperatures. They are also known as rose mallow or swamp hibiscus. They die back to the ground in winter but regrow in spring.
Hibiscus plants have the potential to reach heights of 15 feet or more in ideal conditions, and they can attract pollinators like butterflies and hummingbirds. While many people use them as container plants for landscaping, you can also use them to make herbal tea.
Common Causes of Yellow Leaves on Hibiscus
It takes a bit of detective work to figure out the cause of yellowing leaves. Sometimes, it is just a temporary issue, and other times, it can point to a larger environmental problem. Here are the most common culprits:
- Watering issues: Tropical hibiscus plants need lots of water, but don’t like to be soggy. Too much or too little water can turn the leaves yellow. Water more often (even daily) in heat waves, and less when it’s cool or overcast. Make sure that the plant doesn’t sit in water and that the soil isn’t always wet.
- Soil: Soil compaction, poor drainage, soil moisture, or lack of soil can all be causes behind hibiscus leaves turning yellow. Check your soil’s pH and keep it slightly on the acidic side. Probe the soil around the plant to see if the roots are packed or circling. If you need to repot the plant, use a light and well-draining potting mix, and don’t plant in too big of a container.
- Weather changes: Hibiscus grow best when it’s between the upper 60s and low 80s Fahrenheit. Extreme temperatures, or sudden changes in temperature and wind, can cause the leaves to yellow and drop.
- Environmental changes: Bringing your hibiscus indoors from outside or moving it elsewhere in your garden can temporarily cause the leaves to yellow.
- Light: Hibiscus like to grow in full-sun. A lack of sunlight can yellow the leaves, and too much sun can cause yellow or white splotches.
- Pests: Spider mites and aphids like to snack on hibiscus, causing discoloration in the process. Look for pests on the underside of leaves and clustering near the tips.
- Nutrition problems: Overfertilizing can shock a hibiscus and turn the leaves yellow. Feed the plants lightly and regularly, and check the surrounding soil quality to see if it’s deficient in nutrients. If the leaves are turning yellow with green veins, a condition called chlorosis, it’s a sign of mineral deficiency.
- Chemical shock: Pesticides can yellow hibiscus leaves, especially if they’re applied too heavily or in the heat of the day. Use organic products like insecticidal soaps, and follow package directions exactly.
- Dormancy: Tropical hibiscus often turns dormant in the wintertime. When you bring your plants indoors in the fall, they will likely lose some leaves due to the seasonal and environmental changes.
How to Care for Hibiscus and Prevent Yellow Leaves
Once you’ve sleuthed out the cause of the problem, here are some tips for getting your plant back on track:
- Fix the problem: Fixing the immediate problem causing your hibiscus plants’ leaves to yellow is the obvious first step. Water, repot, move, or protect them to keep growing conditions stable.
- Water properly: Water the hibiscus deeply when the top inch of soil feels dry. Make sure your soil drains well to prevent waterlogging.
- Use the right fertilizer: Use a balanced, water-soluble fertilizer in the growing season, along with a well-draining potting mix for container plants. Mulching around the base of the hibiscus plant can help you conserve soil moisture and lock in nutrients.
- Keep the right temperature: If you’re growing your hibiscus indoors, keep it away from air conditioning or heating vents. For outdoor plants, set up windbreaks or protective covers for extreme hot or cold days.
- Add plenty of light: Hibiscus are full-sun plants, but some afternoon shade may be beneficial to prevent leaf scorch. For indoor plants, use a south-facing window.
- Prune: Your hibiscus plant should start sprouting new leaves once the cause of the yellowing is under control. However, you may want to trim back bare branches to reduce water and nutrient needs through recovery.
Hibiscus problems often take trial and error to fix. Once you find the right solution, your plant should recover nicely.ctacular blooms for years to come. Embrace the learning process and enjoy the beauty these tropical treasures bring to your space.
Frequently Asked Questions
What do overwatered hibiscus leaves look like?
Overwatered hibiscus leaves often turn yellow and may appear limp or wilted. The yellowing typically starts from the bottom plant leaves and progresses upward. In severe cases of overwatering, you might notice brown spots or edges on the leaves, and they may fall off prematurely. The soil might also have a musty smell or show signs of mold growth.
How do I care for Hibiscus plants?
Hibiscus plants thrive in full sun and well-draining soil. Water them deeply when the top inch of soil feels dry, but avoid waterlogging. Feed them with a balanced, water-soluble fertilizer during the growing season. Prune in early spring to encourage bushiness and more blooms. Protect them from cold temperatures and bring tropical varieties indoors during winter in cooler climates.
What are common causes of tropical hibiscus leaves turning yellow?
Common causes include watering too much or not enough. Missing nutrients, pests (like spider mites or aphids), high temperatures, not enough light, or natural leaf aging. Changes in the environment, such as moving the plant or seasonal transitions, can also cause temporary yellowing.
What nutrient deficiency causes yellowing of hibiscus leaves?
Iron deficiency is a common cause of yellowing hibiscus leaves, resulting in a condition called chlorosis. In this case, leaves turn yellow while the veins remain green. Nitrogen deficiency can also cause overall yellowing, starting with older leaves. Magnesium deficiency might cause yellowing between leaf veins, particularly in older leaves.
What should I do if my tropical hibiscus leaves are turning yellow?
First, assess your watering practices and adjust if necessary. Check for signs of pests and treat if present. Ensure the plant is getting enough light but protected from intense, direct sunlight. If you suspect a nutrient deficiency, feed with a balanced fertilizer or consider a soil test. Prune away severely affected leaves and be patient – it may take time for healthy new growth to appear after addressing the issue.
Further Information
- How to Grow Hibiscus (article)
