Bougainvillea is lush, attractive, and relatively easy to care for. Most American enthusiasts will need to grow their bougainvillea in pots, although those in warmer climates may include them in their gardens.
Of course, these are plants, and no plant is totally immune to infestations, including bougainvillea.
What Pests Attack Bougainvillea?
While not considered particularly vulnerable, bougainvillea may be attacked by a variety of pests.
Here are the most common pests, as well as what remedies work best.
One of the most common plant pests, aphids, actually creates three different threats to bougainvillea.
- These piercing insects drink the sap of your plant, which is essentially the plant’s blood.
- This can weaken the plant as well as slowly kill leaves and hinder photosynthesis.
- Secondly, aphid excrement is half-digested sap, called honeydew.
- This sticky substance can lead to powdery mildew and sooty mold.
- And finally, honeydew is a food source for ants.
- The ants will actively protect aphids, which they treat as livestock, from natural predators.
- This not only allows a population explosion it also can reduce the beneficial insect population.
The easiest way to eliminate aphids is using neem (a neem oil foliar spray, neem soil soak, and/or neem cakes).
Washing the leaves with insecticidal soap is also highly effective.
You will only be able to use natural predators on outdoor plants if you first take steps to prevent ants from accessing the plant.
Bougainvillea Looper Caterpillar
Often referred to as an “inchworm” due to the way it bunches up when moving on the leaf surfaces, the bougainvillea looper is a small brown, green, or yellow caterpillar.
These pests chew along the edges of bougainvillea leaves and will also attack tender young shoots.
While they won’t kill a healthy adult, younger plants can be decimated by these loopers.
There’s also a risk of infection and defoliation.
Bougainvillea loopers are resistant to many pesticides, but a couple of natural remedies remain highly effective.
Small birds and carnivorous animals can help reduce the looper population on your outdoor plants.
Neem oil in the form of foliar sprays or soil drenches is an excellent means of combatting these pests.
Finally, Bacillus thuringiensis (or Bt for short) is a natural bacterium that causes loopers and other caterpillars to starve when ingested.
One of the more unusual and easy-to-spot pests is the leaf miner.
Leaf miners are actually the larvae of Diptera, Hymenoptera, and Lepidoptera.
These maggots eat the tender insides of leaves, creating tunnels.
The resulting pale, mazelike lines, paired with an abundance of adult flies, are the two easiest ways to spot a leaf miner infestation.
As the adult fly pierces the leaf to deposit her eggs and the maggots live feeding on the insides, a neem soil soak is by far the best remedy.
The neem oil becomes a systemic insecticide, killing the leaf miners and preventing them from achieving adulthood.
Indoors, fly strips, carnivorous plants, and other common fly killers will help prevent an infestation.
Outdoors, parasitic wasps, and trap crops (plants such as columbine or velvetleaf that draw the flies’ attention) are both excellent options.
Mealybugs are actually a type of scale, and they tend to look like little tufts of cotton.
These piercing insects feed on the sap, creating honeydew in the process.
It’s sometimes difficult to spot them since they live on the undersides of leaves.
Neem oil is once again one of the most effective indoor and outdoor treatment methods.
Natural predators, such as lacewings or parasitic wasps, are also quite deadly to a mealybug population.
Plant scale are an entire group of piercing insects that fe4ed on plant sap.
Many, such as the armored scales, become stationary as adults, creating a protective waxy shell that keeps them safe from most insecticides.
Scale can devastate plants if left unchecked and can also attract other problems due to the honeydew they produce.
Neem soil soaks are one of the most effective treatment methods, as it gets past the barrier and attacks scale from the inside.
You can also attack them directly with a cotton swab soaked in rubbing alcohol.
Natural predators, such as lady beetles and parasitic wasps, can also be an effective solution for an outdoor bougainvillea.
Snails and Slugs
These pests are a valuable part of the ecosystem but can also devastate your flower garden.
Their diet of decaying matter is often supplemented with tasty live plants, such as your Bougainvilleas.
Used coffee grounds are an excellent way to destroy these pests while also enriching the soil.
Just be aware that the used grounds contain plenty of nitrates and can make the soil more acidic.
Shells (such as egg or seashells) and diatomaceous earth (or DE) can be sprinkled on the soil, and all work the same way by shredding a slug as it passes over them.
Beneficial nematodes are yet another great remedy and act as deadly parasites.
Finally, you can create small barriers of wheat or corn bran.
These will kill slugs and snails when ingested and won’t harm any wildlife that cleans up the corpses.
However, bran, much like DE, needs to be reapplied after each rain.
These tiny arachnids feed on plant sap and are often identified by their compact web bridges.
They can be killed easily with neem oil methods, as well as insecticidal soap.
Natural predators, such as lady beetles, are also effective spider mite killers.
Another very common pest you rarely hear about, thrips breed quickly and live on plant sap.
As with most pests, you can kill off a colony using neem oil treatments or insecticidal soap.
Lacewing, ladybugs, and parasitic wasps all love these little monsters and can be a great outdoor control method.