The friendly aloe vera plant (Aloe barbadensis miller, USDA plant hardiness zones 10 to 12) is a popular succulent and indoor houseplant. If you have bugs on your aloe plant, it can be very concerning, but this problem is easily remedied with the right care and products. Among the most common aloe vera pests are scale insects, but you can also find many other unwelcome invaders in aloe plants, including gnats. Similar pests may also be found on other plants, like gardenias (Gardenia jasminoides, USDA plant hardiness zones 6 to 10).
Bugs on Aloe Plants
You can find fungus gnats in aloe plants when the soil is too wet. The adult ones are about 1/8 inch to 1/16 inch long and look like mosquitoes, with slim legs and long antennae. The best way to prevent them is to avoid overwatering. Allow the soil to dry out completely and this should keep them away.
If you suspect that there are gnats in the soil, you can place some sticky flypaper at the soil level. This is most effective when the soil is dry, though. Watering with insecticidal soap or a systemic insecticide can also kill the larvae. Along with the scale, pests who also like aloe vera include red spider mites, mealybugs, snout beetles and gall mites. Insecticidal soaps can also eliminate these pesky insects.
Aloe vera plants must be watered deeply but not too often. The soil should be moist after it is watered but then be allowed to dry out. Let the top third of the potting soil dry out after watering. As a general rule, only water every two to three weeks during the spring and summer and less often in the autumn and winter. If any excess water drains out of the bottom, allow the plant to sit in it for 10 to 15 minutes and discard the water afterward.
Gardenia Pests and Treatments
Fragrant tropical gardenia plants are also prone to certain insects, including pests like the citrus whitefly and melon aphids. Citrus whiteflies are small, flat, white-winged scale insects that coat aloe leaves with sooty mold and honeydew. They can also be found on the bottom of gardenia leaves.
These whiteflies can be sprayed off with a garden hose, but you can also use an insecticidal soap. Just make sure to get the undersides of the leaves and follow up with repeated applications if necessary. Japanese wax scale insects leave waxy white blobs and sooty mold on gardenia twigs and limbs.
Additional Bug Removal Efforts
For Japanese wax scale on gardenias or aloe plants, you may find some success with insecticidal soaps. However, some experts like using horticultural oil. This suffocates the scale insects and should be sprayed on thoroughly until the oil drips off the top. The best time to use this is in the early evening when the temperature is between 45 and 90 degrees Fahrenheit.
Tiny melon aphids may or may not have wings and are recognized by their soft, yellow to dark green bodies and black heads. These can also be sprayed off with a strong water stream, and you can apply insecticidal soap or horticultural oil. Keep checking the plants and if the insects are there, you will have to reapply every few weeks according to the label's instructions.