There’s no denying the beauty of a gardenia in full bloom. Its unique scent is the biggest draw for a generally high-maintenance Gardenia plant. You can immediately tell a person has gardenias by the wonderful scent it gives off.
This beautiful plant is a favorite among gardeners and enthusiasts. But it isn’t as popular as roses due to the high maintenance requirements and disease risk.
Maintaining a gardenia isn’t overly complicated once you get into a rhythm.
Keeping the plant de-stressed through regular care goes a long way towards having a happy, healthy gardenia.
The hardest part is dealing with an infestation and common gardenia diseases.
What Bugs Attack Gardenia Plants?
All Gardenia varieties face several common plant pests that can also affect other plants in your garden.
Some minimally toxic and natural methods can control these pests once you know how to identify them.
Here are the most common pests and for what you may see.
Aphids
The best-known of all piercing insects, aphids are tiny greyish bugs that can quickly overrun a plant.
Aphid populations have a symbiotic relationship with ants, which protect the aphids from natural predators. The ants harvest the aphids’ honeydew for food and leave behind sooty mold.
As aphids tend to hide on the undersides of leaves, you will often first spot an infestation by the presence of ants on the stems and leaves.
Aphids are easy to control using systemic insecticides, neem oil, insecticidal soap, or horticultural oil.
If you place diatomaceous earth around the base of the plant, it will prevent ants from getting to the aphids. Then natural predators such as ladybugs can feast in peace.
More about Aphids on Gardenia Plants
Mealybugs
Mealybugs are among the most common species of scale and have a grey body with white powdery wax covering it.
They are often compared to tiny pieces of cotton. They are yet another piercing insect that sucks plant juices and prefers the underside of leaves.
The good news is that mealybugs have a softer shell than many other types of scale. They can die with neem foliar sprays and other contact methods.
Systemic insecticides are also very useful. Or you can attract a variety of natural predators into your outdoor or greenhouse gardens that will feast on the mealybugs.
Nematodes
Nematodes are a microscopic species of worm that lives in the soil around plants.
These pests feed on the roots, which can cause gardenias and other plants to become stunted or even die.
Because they don’t infest the main body of the plant, most pesticides won’t work on them.
Yet, neem soil soaks and neem cakes are both effective against these pests and will not harm earthworms.
Scale Insects
Plant scale insects are small, potato bug-like insects that secrete a waxy substance that becomes a protective shell.
In some species, this shell makes them immobile, and they spend the rest of their lives glued to the spot sucking plant sap.
The shell is also resistant to most forms of contact insecticide, protecting the bugs underneath.
One of the best methods for killing scale is to dab a Q-tip in either rubbing alcohol or isopropyl alcohol, then to touch each mealybug.
The wax dissolves the scale’s waxy coating and kills them.
Neem oil is also effective but works best when used as soil soak.
It results in a systemic insecticide that bypasses the shell and affects the scale’s ability to eat or reproduce. This leads to a slower but more efficient end to the infestation.
Spider Mites
These tiny cousins of spiders can be tough to see but leave some undeniable call signs.
They live on the undersides of leaves. They produce dense, messy webbing used to protect their eggs and create bridges between limbs and leaves.
Spider mites have bodies small enough that they can float to nearby plants by a decent breeze. You will need to treat those as well, even if they don’t have symptoms.
Systemic insecticides, such as a neem oil soil soak, are effective against them and make for an excellent preventative.
Horticultural oils, insecticidal soaps, and natural predators are also very effective countermeasures.
Thrips
There are over 6,000 known species of thrips, most of which are piercing pests.
Their small size means you’re likely to spot the damage well before you spot the cause.
Even one thrip can be a problem, as they are capable of reproduction without fertilization. They can form swarms that will decimate your gardenias.
Contact insecticides can be less reliable, as thrips are capable of flight for very short distances.
But, an excellent systemic insecticide will decimate a thrip infestation when given a little time to work.
Additionally, natural predators are an excellent resource for combating these pests.
Be warned, thrips can take shelter in furniture. Thus, move any plants to another room after dealing with an infestation.
Whiteflies
One of the most common pests to plague gardenias is the whitefly.
The tiny Citrus whitefly (hence the name) has piercing mouthparts. Like most piercing insects, they produce honeydew, which leads to fungal diseases and sooty mold fungus.
As with many similar pests, whiteflies prefer to hide on the undersides of leaves. It makes them harder for insectivores to spot.
Most pyrethroid contact insecticides work well against whiteflies, as does neem oil.
Acephate is also a proper systemic insecticide to spray onto the upper sides of leaves and soak through to the underside. This makes it harder for the whiteflies to escape contact.