Catalpa bignonioides, aka the Indian bean tree – with its lovely dense green foliage and striking clusters of funnel-shaped, orchid-like white-colored flowers, making it an excellent choice to embellish our backdrops and landscapes.
However, sometimes these green beauties have to suffer from various diseases and pest infestations that can be pretty problematic.
So, today, in this article, we’ll talk all about that!
We are going to learn about different pests and diseases to which the Indian bean tree is susceptible. In addition, we’ll also learn how to control/prevent these problems so that you can take the best care of your plant and keep it as healthy as possible.
Sounds convenient? Let’s get into it!
Pests & Diseases That Affect Indian Bean Tree
Before getting into the main stuff, you should know a couple of things:
You must know that the Indian bean tree is poisonous. As we will discuss different pests and diseases and their control, you’ll need to wear safety gloves while working with this plant.
Also, if you think that your Indian bean tree is suffering from a disease or a pest infestation, you must keep it away from other plants to avoid the spread.
With that said, let’s first talk about the pests!
Indian Bean Tree Pest Infestations!
Following are pests that cause Indian Bean Tree problems
1. Aphids
Aphids are tiny green or brown-black insects that suck the sap out of your plants.
Although these vexatious little creatures suck the life out of your plant — leaving them stunted and deformed, it will require a large mass of them to create a troublesome infestation.
Moreover, they become more hazardous as they can also transmit a good variety of plant viruses.
In fact, they are considered the most destructive plant pests in temperate regions.
If we talk about the Indian bean trees, they have nectar glands under the leaves, which secrete nectar.
As I mentioned, aphids are sap-sucking pests; therefore, they accumulate near the tips of the branches or underside of the leaves where they can find the plant juices (they love the new succulent growth).
If you know about aphids, they are famous for producing honeydew, which is a sugar-rich sticky fluid that can build up on the foliage and result in sooty mold.
Control & Prevention
If the infestation is bad, control won’t be easy!
In small home gardens, soap solutions, neem oil, and high-pressurized water are effective against aphids.
The use of insecticides on aphids does not often produce satisfactory results because of their resistance to various organic and inorganic chemicals.
Therefore, it would be best to consult a plant care professional besides trying home remedies.
Some natural predators of aphids include ladybugs, lacewings, parasitic wasps, hoverflies, flower spiders, and beetles.
To prevent infestation, constantly monitor your plants for the presence of aphids.
If you catch them early, you can effortlessly hose them off with water.
Also, with honeydew production, aphids attract ants. So, if you notice a great load of ants crawling toward your plant, you can catch the infestation.
Planting aromatic veggies like onions and garlic can keep aphids at a distance!
2. Mealybugs
The mode of action of mealybugs — except for the limitations of their morphology — is pretty similar to aphids.
While aphids are green to brown/black insects, mealybugs, on the other hand, are white or pink sap-sucking pests, with their stylets piercing through the plant’s tissue.
They are tiny, wingless pests that appear as white cottony masses on the plant’s foliage.
Mealybugs mostly aggregate near the nodes or at the base of the shoots where the stem branches.
They also primarily appear in warmer climates and produce fluid secretions that can cause fungal growth (sooty mold) on different parts of the plant.
If your Indian bean tree is infected with a crowd of mealybugs, it will show yellowing and curling of leaves, with overall weakened immunity.
Control & Prevention
Predators such as lady beetles are usually effective as natural control. Chemical control involves the use of insecticides or insecticidal soap sprays.
Mature mealybugs are generally resistant to insecticides, while immature ones can be controlled.
These measures are successful only at a low level of infestation. If your Indian bean tree is massively infested, it’s better to eliminate it!
It is best to avoid any kind of pest infestation by taking proper care of the plant.
Keeping weeds at a minimum and maintaining good moisture conditions around the plant is essential.
Inspecting the plant before letting it into the house can prevent a pest invasion.
3. Whiteflies
Whiteflies are also common pests of many plants, including the Indian bean tree.
As the name suggests, whiteflies are white, fly-like, winged insects. They are closely related to mealybugs and aphids.
Plants infested with whiteflies will show symptoms like yellowing of leaves and leaf drops.
Like aphids and mealybugs, whiteflies also produce sooty mold.
Whiteflies are greenhouse pests and cannot usually survive cold outdoor climates.
However, they can become your outdoor seasonal pests if you bring a plant from an infected greenhouse.
That’s why you should always inspect the plants before bringing them in!
Whiteflies are mostly found under the leaves, where they sit and sip plant juices. They love new growth and green parts of the plant. Also, you will see their next generation hatching underneath the leaves.
Noticing a whitefly infestation is easy as they fly in swarms around the plant.
Control & Prevention
Like other pest infestations mentioned before, controlling a high-level whitefly infestation is not a piece of cake.
It is always best to prevent invasion in the first place.
Applying insecticidal sprays and horticultural oils can help lessen the insects but not eliminate them. Nevertheless, using natural enemies will provide you with adequate control of moderate infestations.
Moreover, home remedies such as high-pressure hosing and pruning infected parts of the plant can help you to some extent.
You can learn more about getting rid of these pests by watching this YouTube video:
That was all about the pesky pests! Now, let’s talk about the Indian bean tree diseases.
Indian Bean Tree Diseases!
Plant diseases are much more frightening than pest infestations, but let’s dash ahead and see what we can do about them.
1. Powdery Mildew
Being a gardener, you must have heard about powdery mildew as it affects a wide range of plants.
It is a fungal disease of plants that results in spots and patches of white powdery-like substance on both sides of the leaves.
It also affects young stems, buds, and flowers.
Many different fungal species are responsible for this disease. No less than five species of powdery mildew are reported in the UK, infecting the Indian bean tree.
The spread of the disease is usually caused by spores carried by air.
Young and weak plants are more susceptible to the disease.
Control & Prevention
Control of the disease involves immediate removal of the infected parts of the plant.
Moreover, in the case of acute disease, contact a professional and ensure proper fungicide application.
Protectants and eradicants can both serve a great purpose here.
To prevent the disease, avoid early summer applications of nitrogen fertilizer as it can cause overproduction of fresh green foliage prone to infection. Also, avoid watering overhead to reduce relative humidity.
Adequately spacing the plants while planting and annual pruning will ensure proper air circulation and better lighting conditions for healthy plant growth.
2. Verticillium Wilt
Another widespread disease of Catalpa is Verticillium wilt.
It is considered a fatal plant disease as it causes blockage of the xylem and phloem tissue, diminishing the water and nutrient flow and leading the plant to wilt.
Several Verticillium fungal species cause the disease.
Sudden yellowing, wilting, and dying of leaves are the symptoms.
Young plants or parts of the plant are instantly killed by the disease, while healthy plants can survive longer.
Control & Prevention
The disease is usually not curable.
However, the plant’s life can be increased by taking care of watering and fertilization.
Still, depending on your plant’s health, it can survive for maybe a year or more.
Remove the dead and decayed parts of the plant and avoid adding them to compost.
You must not plant susceptible varieties in your garden to prevent the disease. Also, do not grow another Catalpa in place of a diseased plant.
3. Leaf Spots
Both bacteria and fungi can cause leaf spots.
They come in various sizes, shapes, and colors. They can be brown, black, or yellow (viral — Catalpa chlorotic ringspot) spots or patches. They can be circular with smooth edges or ragged fringes.
Depending upon the cause of the spread, they might be present on the upper, lower, or both sides of the leaves.
Insects, rain, air, contaminated tools, and humans can cause its spread.
Control & Prevention
Remove dry and infected plant parts.
Rake up fallen leaves and get rid of them to prevent the spread. Wet and humid conditions provoke its spread. Therefore, try not to water overhead or splash water here and there.
Prevent overcrowding and ensure proper pruning to increase airflow.
Using a fungicide is unnecessary if all the leaves are not affected repeatedly over the years. If so, use recommended fungicide according to the labeled directions before the symptoms appear.
Moreover, you can hire a professional arborist for the job!
We hope you liked this article highlighting Indian Bean Tree problems and diseases.
We’ve compiled this post after extensive research on the matter. Therefore, we hope it proves to be helpful!
