Have you noticed ants ‘attacking’ your garden plants? Are the leaves on your plants becoming discolored, and, if left long enough, curling up on themselves? Do they look as if they have ash or soot all over them? If you have seen any of these signs in your garden, you may want to check your plants for aphids.


1280px-Aphids_on_Helleborus_nigerAn aphid is a small, soft-bodied, sap-sucking insect that can be green, yellow, black, brown, red or even clear. These small insects feed passively on plants, specifically by sucking out the sap. The signs of aphid infestation can be any of the following.

  •  Sticky substance on leaves
  •  Leaves slowly starting to turn yellow
  •  Leaves start to distort, can even roll up on themselves
  •  Stunted plant growth
  •  Black substance on leaves. This black substance is known as Black Sooty Mold 
  •  This mold only grows on honeydew, and looks as if the plant has been sitting near a bonfire and soot has covered it. If you treat the bug causing the honeydew, this mold can be washed off easily.
  • Another great indicator is the sight of ants.

The Ants Come Marching One By One..

If you see ants on your plants, they are not the ones causing the damage. In fact, they are cleaning up the mess produced by aphids by eating the extracted honeydew. These smart insects will protect aphids from natural predators by fighting them off, and even bring aphid eggs into the ant colony to survive the winter. Ants have also been known to move aphids onto other plants, to ensure a constant food source for themselves. Ants have even been seen ‘milking’ aphids for honeydew!

If left to their own devices, aphids will deform and stunt your plants. If left long enough they will produce black sooty mold and aphids can be active carriers of viruses that can be lethal to plants. Due to these factors it is best to control them.

Aphid Controls

Natural Predators


ladybug larvae feedingLadybug larvae are a natural predator of aphids. One ladybug larvae can feed on up to 5,000 aphids! You can attract ladybugs naturally to your garden with the following plants:
Fern-Leaf Yarrow
Butterfly Weed
Carpet Bugleweed
Spike Speedwell

Read more about the ladybug here:


lacewing larvae

Often referred to as the “aphid lion,” a single lacewing larvae can consume up to 200 aphids a week. The best part about these larvae is that their taste extends beyond just the aphid; spider mites (especially red mites), whitefly, mealybugs, thrips, leafhoppers, and some forms of beetle and moth larvae are also on its menu.



You can attract lacewings naturally to your garden with the following plants.

  • Bee Balm
  • Catmint
  • Liatris
  • Butterfly Bush

Read more about lacewings here. 

Ant Control

1024px-Ant_feeding_on_honeydewAnts have a symbiotic relationship with aphids and will fight off their natural predators to the death. Help keep your ladybugs and lacewings alive by controlling the ant population. For trees and shrubs, use a banding tape around the base of the plant. This is a double-sided tape that is safe for plants. The tape prevents ants from being able to walk up the base of the plant, as they will get stuck on the tape. You can also use a product called diatomaceous earth. Sprinkle this on the ground around the base of the plant and it will kill the ants on contact. Take care not to apply this to the leaves, as it can also kill the beneficial bugs you are trying to save.

Decoy Plants

Did you know there are some plants that actually attract aphids? Plant these away from your main gardens to attract aphids to them.

  • Larkspur
  • Hollyhock
  • Chrysanthemum
  • Aster
  • Nastursium
  • Cosmos
  • Zinnia

One of our workers actually tried this in her vegetable garden. She planted up nastursium in clay pots and placed them about 3-4′ from her vegetable garden. While the nastursium had many aphids, there were very few aphids on the vegetables.

Spray Control

Garden Hose

Sometimes a strong spray from your garden hose is all you need. Blast those suckers off! Once knocked down, the aphids are incapable of getting back up. Spray your plant daily until all aphids are gone.

Insecticidal Soap

Sometimes aphids can appear from left-field and your plant is heavily covered. If all other methods have not worked you could use insecticidal soap. You need to spray the underside as well as the top of the leaf, as aphids like to hide underneath. Apply this once every 2 weeks until all aphids are gone. Take note that insecticidal soap will also kill beneficial bugs like ladybug and lacewing larvae, so check your plants first to see if these critters are already there working before resorting to insecticidal soap.