Whiteflies target both indoor and outdoor ficus plants.

How to Treat a Whitefly Infestation on a Ficus

by Jessica Westover

With more than 800 varieties of ficus (Ficus spp.) available for cultivation, you have a wide selection to choose from. Ficus plants, also known as ornamental figs, range from trees and shrubs to vines, and grow well outdoors in the ground or indoors as potted plants. Depending on the specific variety, ficus plants grow in U.S. Department of Agriculture plant hardiness zones 6 through 11. Occasionally, whiteflies, white mothlike 1/10-inch-long insects, attack ficus leaves, sucking the sap from individual cells. If left untreated, whiteflies eventually cause defoliation. Treat whitefly infestations in your ficus with neem oil or traps.

1. Neem Oil

1 Put on a long-sleeve shirt, pants and gloves to protect your skin from direct contact with the neem oil. Wear a hat and use eye protection to shield your eyes from the insecticide.

2. Neem Oil

2 Remove the lid from a tank sprayer. Pour 1 gallon of water into the tank. Add 2 tablespoons of neem oil to the tank. Stir the ingredients with a stick to combine them thoroughly.

3. Neem Oil

3 Screw the lid on the tank tightly. Pump the tank's pressurizing handle up and down until it becomes difficult to do so.

4. Neem Oil

4 Point the sprayer's tip at the ficus plant's infested foliage, keeping it 6 inches away from the leaf surfaces. Press the button to release the neem solution. Move the wand back and forth evenly to coat the top and bottom surfaces of the leaves completely. Stop spraying once the solution begins to drip off the leaves.

5. Neem Oil

5 Shake the tank up and down every one to two minutes while spraying to ensure that the neem oil remains mixed with the water. Continue to spray the solution, coating all of the ficus leaves. Stop spraying and mix additional solution if needed.

6. Neem Oil

6 Spray the ficus foliage every seven to 14 days in the same manner as before. Stop applications once the ficus tree is free of whiteflies.

7. Traps

1 Cut out a 12-by-6-inch strip of cardboard or poster board with a pair of scissors. Cover a flat work surface with newspaper. Lay the strip on top of the newspaper.

8. Traps

2 Brush yellow paint onto the cardboard or poster board strip using a paintbrush. Use long, even strokes to cover the surface completely. Leave the strip to sit until the paint dries completely.

9. Traps

3 Punch a hole in the strip with a hole punch. Position the hole 1/2 to 1 inch below one of the 6-inch-long edges, centering it. Cut an 8- to 12-inch-long length of string using scissors. Thread one of the string's ends through the hole and tie it in a knot to secure it in place.

10. Traps

4 Pour 1 part petroleum jelly or mineral oil and 1 part liquid household detergent into a bowl. Stir the ingredients together with a spoon. Brush the sticky solution onto the yellow surface of the strip with a second paintbrush.

11. Traps

5 Wrap the loose end of string around one of the plant's branches so that the yellow, sticky side of the trap faces the infested portion of the plant. Tie the string in a loose knot to hold the trap in place.

12. Traps

6 Check the trap every three to four days. Once it becomes filled with whiteflies, untie the trap from the plant. Wipe the sticky solution and trapped whiteflies off the trap's surface with a damp paper towel. Discard the paper towel in a trash bin. Brush on more sticky solution and re-hang the trap on the plant if it remains infested. Repeat this process until all whiteflies disappear.

Items you will need

  • Long-sleeve shirt
  • Long pants
  • Gloves
  • Eye protection
  • Hat
  • Tank sprayer
  • Neem oil
  • Stick
  • Newspaper
  • Cardboard or poster board
  • Scissors
  • Yellow paint
  • 2 paintbrushes
  • Hole punch
  • String
  • Petroleum jelly or or mineral oil
  • Liquid household detergent
  • Bowl
  • Spoon
  • Damp paper towel

Tips

  • Apply the neem oil during the early morning hours when the leaves contain the most moisture to avoid damaging or burning the foliage.
  • Store the bottle of neem oil in a dark, dry room out of the reach of children and pets. Place the bottle in an area with a constant temperature above 40 degrees Fahrenheit but less than 80 degrees. Position the bottle away from food preparation or storage areas and open flames.
  • Layer three to four sheets of newspaper on top of one another, and wrap the newspapers around the empty bottle of neem oil. Discard the bottle in a trash bin.
  • Instead of making your own traps, you can purchase disposable sticky yellow traps from a garden center or plant nursery.

Warnings

  • Never mix more solution than you will use during a single spraying.
  • Use the neem oil solution within two hours of mixing.
  • Do not spray during rainy or windy weather or when temperatures drop below 40 degrees or rise above 80 degrees.
  • Wash your clothes after you wear them for spraying. Wash your skin immediately with soapy water after spraying the oil to remove any traces of it from your person.
  • Do not apply neem oil to stressed ficus plants.

Photo Credits

  • Hemera Technologies/PhotoObjects.net/Getty Images