DIY Killing Aphids

Aphids, a common garden pest, attack plants and harm them by cutting into various parts of the plants and sucking out the moisture. They are also carriers, spreading plant diseases from one location to another. Homeowners often use do-it-yourself remedies that are more effective than commercial remedies. Home remedies are often safer to handle and are gentler on the environment.

Things You'll Need

• Garden hose
• Sprayer attachment
• Water
• Dishwashing liquid
• Cooking oil
• Funnel
• Spray bottle

Instructions

Plain Water

1. Locate the infestation so that you can treat not only the affected plants but the surrounding area as well. Other plants in other areas may be infested as well.

2. Affix a sprayer attachment to the end of your garden hose.

3. Spray across the top of the plants with enough pressure to remove the aphids, but be careful that the pressure is not so strong it damages the plant.

4. Spray the undersides of the plants the best you can. Aphids need to be removed from underneath the leaves as well.

Insecticidal Soaps

1. Mix up an insecticidal soap with household products rather than purchasing a commercial product. Mix a teaspoon of dishwashing liquid in a cup of water. Add a few drops of cooking oil.

2. Funnel the mixture into a handheld spray bottle.

3. Spray the plants and surrounding area thoroughly with the insecticidal soap, both topside and underside.

4. Repeat the application as often as is necessary.

Natural Enemies

1. Obtain a sufficient number of lady beetles. It takes a large number to be effective. According to the University of California's Integrated Pest Management, you will need two applications of 1,500 lady beetles each, applied at an interval of one week, to control the aphids on a single rose bush.

2. Keep lady beetles refrigerated and mist them once a week lightly with water until you are ready to use them, but use them promptly so that they do not die. Shelf life of the lady beetles will depend on their age when purchased. Live lady beetles are available at some garden centers.

3. Release lady beetles on the ground underneath plants and in the crooks where shoots branch off.

Tips & Warnings

• Aphids exude a sticky substance called honeydew. Aiming a spray of water on the leaves not only knocks the aphids off the plant, but it also rinses away the honeydew.

• Don't use lady beetles on plants that have been treated with insecticides. They are vulnerable to these substances just as the aphids are.

• Use any insecticidal spray carefully. Too strong a mixture could harm the very plant you are trying to protect.

References

• University of California Agriculture and Natural Resources: Aphids
• Oregon State University Extension: Using Home Remedies to Control Garden Pests
• Colorado State University Extension: Insect Control: Soaps and Detergents
• University of Florida Extension IFAS: Clean Up Pests With Soap
• University of California Agriculture and Natural Resources: Lady Beetle Releases for Aphid Control: Lady Beetle Releases for Aphid Control: How to Help Them Work

Resources

• University of Illinois Extension, The Bug Review: Aphids