Aphids feed on firebush leaves. Ladybug larva feeds on aphids.

Aaaahhhh – Aphids!

Aphids are a very common garden pest. They feed by piercing leaves and sucking out the juices. This can cause leaves to crinkle and curl, especially on new flushes of growth.

 

Aphids excrete a fluid that contains a lot of sugars. At first, leaves may look wet and shiny from this coating of “honeydew.” But those sugary excretions can lead to growth of unsightly sooty black mold on plant leaves.

Sooty black mold coating leaves.

Sooty black mold on Ixora. Photo Credits: UF/IFAS Kim Gabel

 

Aphids can also be a vector for plant viruses – moving diseases from infected plants to healthy ones.

Sounds pretty bad, right?

 

BUT… before you panic and reach for the insecticide spray or dust, READ THIS:

 

Aphids can usually be controlled WITHOUT using heavy-duty, broad-spectrum pesticides.

 

That’s right. Controlling aphids can be as easy as spraying them with water, or even doing nothing at all!

Here are some simple tips for controlling aphids and their damage –

 

1. Scout plants often. Watch for telltale signs of aphids including:

  • Plentiful small, soft-bodied insects huddled along stems or leaves.
  • Shiny, sticky leaves covered in “honeydew” secretions.
  • Leaves covered in black sooty mold.
  • Puckered, curled, or stunted new growth.
  • Ants that are busy patrolling and “farming” aphids. (Some ants will feed on aphids’ honeydew secretions.)
Aphids cluster tightly around a stem.

Check stems and undersides of leaves. Aphids can vary in color and are often well-hidden.

 

Note: If you think you’re seeing aphid damage, but you don’t actually see the insects, check the undersides of the leaves and stems. Aphids will often stay hidden within the overhanging edges of curled or puckered leaves, or cluster tightly on stems. Another possibility is that the infestation is already over, but the damaged growth remains.

 

2. Check for the presence of beneficial predator insects. Ladybeetles (a.k.a. ladybugs) and their larvae, lacewing larvae, syrphid fly larvae, and predatory wasps are among the many insects that will show up to feast on the juicy, slow-moving, sugar-filled jellybeans. Also, look for aphid “mummies” that were killed and parasitized by tiny beneficial wasps. If the “good bugs” are already on the scene, let them do their thing!

Juvenile ladybeetle on underside of leaf

Learning to recognize all life-stages of the “good bugs” is important. You wouldn’t want to accidentally kill this juvenile ladybug patrolling the underside of a basil leaf. (Photo credit F. Galdo – UF/IFAS)

 

Lacewing eggs and larvae showing hunting behavior

Lacewing larvae earn the nickname “aphid wolves” due to their huge appetite. Left: Delicate lacewing eggs attached to a blade of lemongrass. (Photo credit – F. Galdo UF/IFAS.) Right: Lacewing larvae hunting for pests and wearing the carcases. Photo credits L. Buss – UF/IFAS.

 

3. If the “good bugs” haven’t arrived yet, use a blast of water from a garden hose (or even a sink sprayer for small potted plants) to knock off as many aphids as you can. (Remember to focus your efforts on the undersides of leaves where most of the aphids are hiding.)

 

4. If tender new growth is severely stunted and heavily infested, it may be easier to trim back some of the worst-affected branch tips. (Dispose of them in the trash!)

 

5. If you’re unable to bring your aphid issue under control with forceful water blasts and beneficial insects, horticultural soaps can potentially be effective treatment options. Just be careful to follow the label instructions, and watch for non-target insects.

Milkweed with monarch caterpillar and aphids in close proximity.

Milkweed is a common plant in pollinator gardens – and a common target of milkweed aphids. Spraying anything to control the aphids could harm the caterpillars too, so it’s best to either let the “good bugs” handle this, or use a simple spray of water.

 

For more information about horticultural soaps and other natural pest management strategies, check out the UF/IFAS publication “Natural Products for Managing Landscape and Garden Pests in Florida.”

 

REMEMBER: Aphids have A LOT of natural predators. (What bug wouldn’t love to slurp up plentiful, juicy, slow-moving, sugar-filled jellybeans?) But broad-spectrum pesticides can’t differentiate between “good bugs” and “bad bugs.” If you’re regularly using strong, broad-spectrum pesticides in your garden, you’re killing off all the “good bugs” along with the bad. Guess which population will recover quicker? That’s right – the pests.

Want to learn more about attracting beneficial insects to your garden? Check out the post – “How do I attract the “good bugs?””

 

Juvenie and adult ladybeetles feast on aphids.

The new growth of this firebush was heavily infested with aphids. (Note the curled leaves and shiny honeydew?) BUT – put away the insecticides and have no fear – the “good guys” are already on the scene! (Photo credit – F. Galdo – UF/IFAS)

 

Is something bugging your garden? If you have concerns about garden pests, ask us – UF/IFAS Extension and your local Master Gardeners are here to help! Show us some photos or bring in a sample. Our office can be reached at 352-518-0156.

(Not in Pasco? Not a problem! Click here to find your local UF/IFAS Extension office!)

 


About the Author: As the Florida Friendly Landscaping (FFL) Program Coordinator in Pasco County, Frank works with the residents, homebuilders, and businesses of Pasco to achieve attractive, resilient yards and communities while reducing over-reliance on irrigation, fertilizer, and pesticides. Through an innovative collaboration with Pasco County Utilities, Frank provides on-site assistance to individuals and communities identified as high water users. He can be reached at (813)929.2716.

Thirsty for more FFL knowledge? Check out some of my previous posts!

 


About UF/IFAS Extension: UF/IFAS Extension serves as a source of non-biased, research-based information for the residents, businesses, and communities of Florida, providing educational materials and programs for adults and youth. We proudly “provide solutions for your life.”

Come learn at one of our workshops! Check out our Eventbrite page for a list of upcoming events: bitly.com/eventbritepasco

UF/IFAS Extension Is An Equal Opportunity Institution.

 

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