Aphids are tiny pests that can cause significant damage to both outdoor garden plants and indoor plants. Their ability to reproduce rapidly means an aphid infestation can get out of hand if not addressed promptly.
Approximately 5,000 species of aphids are in the family Aphidoidea, all of which feed on plant sap. They tend to live in colonies with hundreds or thousands of individuals.
When populations become too large or food sources run low, aphids can produce offspring with wings that disperse to new plants for feeding. Aphids can feed on every part of a plant, including the roots.
This comprehensive guide will provide valuable information on identifying, preventing, and getting rid of aphids permanently. We will also cover the most common species, their lifecycle, and the damage an aphid infestation can cause so you can get rid of them quickly.
Identify Aphids
Aphids are members of the insect order Hemiptera, which are small, pear-shaped insects. They are 2 to 4mm long and can be in multiple colors, including green, black, brown, and pink.[1]
Adult aphids may or may not have wings. Aphids feed on plant sap, and their presence can be detected by the sticky residue, known as honeydew, they leave behind. This honeydew can lead to the growth of black sooty mold, further harming your plants.
Types of Aphids
There are over 5,000 species of aphids, each preferring specific plants. The green peach aphid, rose aphid, and cabbage aphid are just a few examples.
However, regardless of species, the damage they cause and the control methods used to eliminate them remain relatively consistent. The table below covers the most common species in your garden or on ornamental plants.
| Name | Coloration | Host Plants |
| Green peach aphid (Myzus persicae) | Wingless individuals are a pale yellow-green or pink; winged individuals have a black head | Many vegetables, flowers, fruits, and woody ornamentals |
| Cabbage aphid (Brevicoryne brassicae) | Gray-green color that can look gray to white due to the waxy secretion that covers their body | Cole crops and other plants in the mustard family |
| Melon (cotton) aphid (Aphis gossypii) | Variable in color from yellow to green to black | Cucurbits, citrus, carrot, flowers, and woody ornamentals |
| Bean aphid (Aphis fabae) | Dark green, brown, or black | Legumes, woody ornamentals, and flowers |
| Potato aphid (Macrosiphum euphorbiae) | Pale to bright green with a large brownish spot on the top of their abdomen | Potato, tomato, spinach, lettuce, and many others |
| Crapemyrtle aphid (Sarucallis kahawaluokalani) | Pale yellow-green with black spots on their abdomen | Crape myrtle |
| Rose aphid (Macrosiphum rosae) | Green, pink, or purplish | Roses |
Aphid Life Cycle
Aphids have complex life cycles with many variations. They go through incomplete metamorphosis. Immature aphids look similar to adults and don’t go through a pupal stage. Instead, they molt several times, shedding their skin as they grow until they reach sexual maturity.
Female aphids can give live birth to offspring with or without wings. They often produce wingless female offspring until populations get too high or food sources are depleted[1]. They have males near the end of the plant growing season in the fall. They can then mate with males and produce eggs that survive the winter.
Aphids produce as many as 12 offspring per day. New offspring mature into adults and start reproducing in as little as seven days. That means a single aphid can become more than 7,000 in at least two weeks.
What Aphid Damage Looks Like
Aphids cause damage by sucking sap from plants, weakening plants, and hindering their growth. Signs of aphid damage include:
- Curling or yellowing leaves.
- Stunted growth.
- A sticky substance on the leaves or beneath the plants.
In severe cases, an aphid infestation can cause the leaves and stems to turn black due to sooty mold growth.
The most detrimental damage caused by aphids is through disease transmission. A single aphid must only feed on a plant for a few minutes to transmit certain diseases[1]. Disease transmission often leads to significant damage or death to plants.
How To Prevent Aphids
Prevention is critical in aphid control. Regularly inspect new plants for signs of aphid presence before introducing them to your garden or home. Aphids tend to prefer new growth, so balanced feeding of your plants can prevent excessive new growth that attracts aphids.
Introducing natural predators, like ladybugs and lacewings, who feed on aphids, is another way to control aphids.
Aphid Control Methods
There are several effective aphid control methods when it comes to getting rid of aphids.
Natural Ways to Kill Aphids
For a mild infestation, you can remove aphids by hand or use a spray bottle to spray your plants with a strong stream of water, which can knock the aphids off the plants.
Introducing or encouraging the presence of natural predators, such as ladybugs, lacewings, and certain species of wasps, can also help control the aphid population.
Homemade Aphid Control
A homemade aphid spray, such as a mixture of water, mild dish soap, and neem oil, can be an effective and eco-friendly way to kill aphids. This mixture can suffocate aphids, disrupting their feeding and killing them. Be sure to spray or wipe every part of the affected plants for it to work effectively.
Chemical Control
If the infestation is severe, you may need to resort to insecticidal soaps, oils, or other chemical insecticides. While these can be effective against aphids, they should be used judiciously to avoid harming beneficial insects or plants.
Get Rid of Aphids Naturally on Indoor Plants
Aphids on indoor plants can be a nuisance. Using a damp cloth to remove aphids manually or applying homemade neem oil spray can be an effective way to get rid of aphids naturally on indoor plants.
Frequently Asked Questions
There are several ways for aphids to infest indoor plants. Some plants may already be infested when you bring them into your home since they can be difficult to detect until populations are large. Winged aphids can enter the home through open doors and windows. You or your pets may also bring these tiny critters into the home unknowingly.
Root aphids can be a serious pest of indoor plants since they live in the soil feeding on roots. However, even root aphids cannot live for long in potting soil. They rely on plant tissue sap to survive and will die within a few days in the absence of the plant hosts to feed on.
Most plants can easily recover from the damage aphids cause to their tissue. However, the bigger concern about aphids is their ability to transmit plant disease. If an aphid introduces a disease to your plants, depending on which disease it is, they may not recover.
Due to aphids having wings, it is nearly impossible to keep them from coming back. The only way to ensure they don’t harm plants in your garden is to grow plants under row covers. For many plants, this isn’t possible. Fortunately, most plants recover from the feeding damage caused by aphids.
Aphids can cause aesthetic damage to plants but typically don’t harm them. However, they are harmful if they transmit plant diseases when they feed. Luckily, unlike mosquitos and ticks, aphids do not cause any type of harm to humans or pets.
References:
[1]Flint, M. L. (2013). How to manage pests: Aphids. UC IPM Online. Retrieved October 21, 2022, from http://ipm.ucanr.edu/PMG/PESTNOTES/pn7404.html