Hibiscuses are well-known for their vibrant and colorful trumpet-shaped blooms with a long, prominent pistil.
They’re available in a variety of colors, ranging from fuchsia pink and magenta to yellow, orange, white, and even dark purples, too.
Hibiscus trees may be the “supermodels” of the plant world, but they’re susceptible to insect infestations just like any other living plant.
If you’ve woken up one morning to discover that your once-healthy leaves are now full of ragged holes and your hibiscus is now dying—quite frankly, you’ve got an insect problem.
Each different kind of insect requires a different treatment method.
Yes, you can use broad-spectrum insecticides, but they will kill beneficial pollinators as quickly as they do the unwanted pests. It’s better to use a gentle insecticidal soap or horticultural oil like neem oil.
Here are the most common insects that love to make a lunch out of the leaves of your beautiful, tropical hibiscus.
What Is Eating the Leaves of My Hibiscus?
If the leaves of your hibiscus have been eaten, it could be insects such as the hibiscus sawfly, aphids, whiteflies, or Japanese beetles. Each has its own control methods, but you can use the hose, insecticidal soap, neem oil, or diatomaceous earth for general prevention methods.
Common Insects That Love to Eat Hibiscus Leaves
There are many different species of insects that love to eat hibiscus leaves.
This phenomenon makes your poor hibiscus tree look like a skeleton and will quickly kill it. However, other insects simply chew holes or suck the nutritious sap out of hibiscus leaves, leaving them damaged and wilting.
The most common pests that love to feast on a hibiscus are:
We’re going to discuss the hibiscus sawfly, whiteflies, aphids, and Japanese beetles in this article and how to prevent them from munching on your poor hibiscus tree’s leaves.
The hibiscus sawfly isn’t picky and will feed on a wide variety of cultivars. Their name contains the word “fly,” but they’re actually a close relative of bees and wasps.
You can quickly identify these pests as adults because they are all dark, except for a single, orange-colored dot that’s present on their upper thorax. The caterpillar-like larvae have greenish-yellow bodies with a red, purple, or white stripe right down the sides.
When the adults are ready to lay eggs, they choose the underside of hibiscus leaves as one of their favorite nurseries. Once the larvae hatch, they go to work.
When they’re done, all that will be left is the skeleton of ribs and veins. No leaf tissue at all will remain, similar to a lace-like pattern.
Control Methods for Hibiscus Sawfly
You can get rid of these pesky sawflies by the best and most original method ever, which is handpicking and then squishing. You can also put them into a bucket of soapy water if you’re too squeamish about squishing the larger adults.
Unfortunately, the larvae may look like caterpillars, but they’re actually worms, so using natural bacteria like Bt (Bacillus thuringiensis) won’t work. Instead, try insecticidal soap or horticultural oil. Spray early in the morning or right before dusk.
You can also try using neem oil (or another pyrethrin) mixed with canola oil, which is another effective control method. Reapply frequently throughout the growing season.
Or, try using hibiscus fertilizer mixed with diatomaceous earth, which can be used long-term but may also harm other beneficial insects.
Maybe you’ve never heard this term before, but aphids are often referred to as “plant lice.” That’s because they use their mouthparts to spit in digestive juices and then break down the plant’s nutritious tissue, then suck it back in as their meal.
In high numbers, they can be very damaging. Aphids are small, leggy, green bugs that leave a very sticky “honeydew” (a.k.a. aphid excrement) on the leaves of your plants.
They can also cause yellow leaves or cream-colored spots, leaf curl, and turn leaves and new growth brown and dead. They’re also dangerous because they can carry diseases that will kill your hibiscus.
Control Methods for Aphids
There are a few different control methods that are effective against sap-sucking aphids. For an all-natural approach, use a jet of water to simply spray them away.
They’ll drown under the onslaught of the hose, and the ones that survive won’t be able to find their way back to your hibiscus tree.
Another method is using horticultural oil like neem oil. Aphids aren’t the hardiest insects, and either the oil or insecticidal soap will be an effective control method for them.
If you prefer chemical insecticides, try using pyrethrum. Mix it with a pint of rubbing alcohol, and then use it as a spray on your plants. Use it regularly for maximum protection.
You can also use Diatomaceous earth on the leaves and stems of your hibiscus. However, remember that it can harm beneficial insects, too, so use it sparingly.
Japanese beetles may be a beautiful iridescent green-blue-brown color, but the damage they can do to your hibiscus plant leaves is not so attractive.
Hibiscus is a favorite treat of Japanese beetles, and they will be all too happy to munch away happily until the leaves are full of holes.
If you live anywhere except for Japan, Japanese beetles are an invasive species that can take over if left unchecked. In fact, they’re another pest that will eat the tissue of the leaves and only leave the ribs untouched.
The leaves of your hibiscus will look lacy, and the beetles will be feeding most voraciously in the morning and early evening.
Control Methods for Japanese Beetles
Keep in mind that Japanese beetles actually have a pheromone that will attract other beetles, so seeing one is usually a harbinger for more to come.
That’s why it’s essential to use effective control methods to stop these pesky leaf-eaters. The best approach is to pick them by hand and drop them into a bucket of soapy water.
In fact, these beetles will simply clench up and drop when disturbed, so all you have to do is shake the leaf and hold the soapy water bucket underneath.
But, what happens if you have a large crop or a very bad infestation? Well, this method can call for pesticides.
While many options will effectively kill Japanese beetles, they’ll also kill beneficial insects too.
The best choice is a neem oil or a gentle insecticidal soap. To provide effective control, these should be sprayed directly onto the beetles.
Whiteflies are another common pest who are all too happy to infest your hibiscus and eat the leaves. They prefer the underside of the leaf, and similar to aphids, they’ll suck the sap right out of the plant and essentially starve it to death.
You can identify these tiny white flies by shaking the plant. When they’re disturbed, they’ll form large clouds at about eye level that will have you swatting the air in annoyance.
Adult female whiteflies will lay up to 400 eggs on the undersides of the leaves, which can all hatch, with your hibiscus ready and waiting as their first meal.
Remember how we just said that whiteflies are similar to aphids? Well, aside from the fact that they look like tiny white flies instead of green, leggy insects, they form the same sticky honeydew excretion that aphids do.
This honeydew can form an ashy-looking black mold that will grow on the leaves, too. While they won’t necessarily kill your hibiscus, they’ll stunt its growth and make it look very unpleasing.
Control Methods for Whiteflies
Whiteflies may be a common pest of hibiscus, but they can be easily controlled if you know what to do.
As always, if there are only a few of these pests on your hibiscus, you can easily hand pluck them off and put them in soapy water or squish them. However, larger infestations call for different control methods.
You can use the garden hose to forcefully spray them off. Remember, whiteflies like the undersides of leaves, so pay close attention and be sure that you spray weekly. This can also help remove those ashy, black moldy spots on the leaves too.
While you can always use pesticides, remember that they may harm or kill beneficial insects or pollinators. Instead of insecticides, use pruning shears to clip off the infected leaves. Dispose of them in the trash instead of the compost pile.
One other method is using sticky traps, which will trap the whiteflies. Make them out of wooden frames. Paint them yellow to attract the whiteflies. Once they’re dry, use a mixture of dish detergent (like Dawn) and petroleum jelly as the “sticky” part.
Put the sticky traps in the garden or by your potted hibiscus to trap whiteflies. You can encourage the flies into the traps by disturbing the leaves, so they fly right into the sticky part.
Hibiscus are beautiful ornamental trees that get quite big and can make any bland deck or patio pop with color. These tropical flowers have gorgeous, vibrantly colored leaves that come in a range of colors.
If there are holes in the leaves of your hibiscus, the cause is an insect infestation. The most common pests that love to munch on hibiscus leaves include hibiscus sawflies, whiteflies, aphids, and Japanese beetles.
You can control these pests with a variety of methods, including insecticidal soap, neem oil, handpicking, or by spraying the leaves with water every week.
With these control methods, you’ll be enjoying the beautiful and bright blooms of your hibiscus for a long time.
While you can always use pesticides, remember that they may harm or kill beneficial insects or pollinators.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.