Tuesday, March 20, 2012

Whitefly Remedy

I'm having trouble with whiteflies in the greenhouse. My citrus trees are covered with them, and they're beginning to take their toll on the plants.
Whiteflies are similar to aphids: they are tiny white flies (duh) that feed by sucking the sap from plants. In the north they die off during the cold weather (though greenhouses still can have this problem due to the warm temperatures), but here in the south they are a year round pest. They are found on the undersides of leaves and fly into the air in white clouds when disturbed.
  Whiterflies attack the plant by sucking it's juice, causing leaves to turn yellow and fall, but they also secrete a sticky substance that attracts black, sooty mold which interferes with photosynthesis.

 Here you can see the curled, dying leaves and the black sooty mold covering them - in contrast to new, undamaged leaves above.

My problem is this: I would spray them with chemicals to save my citrus, but also in our greenhouse is a swimming pool filled with tilapia fish which are highly sensitive to pesticides.

Here's a solution that I hope will help - two homemade remedies that I plan to make and use this afternoon.

The first is Yellow Sticky Boards. Apparently whiteflies are attracted to the color yellow so I will paint pieces of cardboard yellow and coat them with a sticky substance. I have petroleum jelly on hand so I will use that - a homestead motto - USE WHATCHA GOT!  Then I'll hang these from the infested trees. Hopefully this will trap the adults.

The second is a homemade, insecticidal soap:
  *one gallon water
  *2 t baking soda
  *2 t dish detergent 
  *2 t white vinegar
Spray this solution under the leaves of your plants where the white fly eggs, scale and adults reside.
In order for it to be effective, each leaf must be sprayed.
Repeat every 3-5 days until  pests are eradicated

I'll let you know how it works.
And I'm open for any and all advice - always. About everything!

1 comment:

  1. I read this... you probably did, too... following manufacturer instructions is one option. Whiteflies are also attracted by the color yellow so yellow sticky paper can serve as traps to monitor infestations. Dead leaves or leaves that have been mostly eaten by whiteflies can be removed and burned or carefully placed in closed bins to avoid reinfestation and spreading of the disease.
    Early detection in combination with hosing or vacuuming of diseased portions as well as removal of any section that is heavily infested. Pesticide use is not ideal in the case of controlling whitefly and widespread contamination can be costly; it is best to avoid this problem with aggressive preventive measures.
    Several predators and parasitoids may be effective in controlling whitefly infestations. These predators include green lacewings, ladybirds, minute pirate bugs, big eyed bugs, and damsel bugs.
    Integrated management of whitefly can as well be done using Biopesticides based on microbials such Beauveria bassiana (effective on nymphs and adults) or Paecilomyces fumosoroseus.
    Green lacewing larvae have a voracious appetite. They will attack whiteflies as well as other pests including aphids, mealybugs, spider mites, leafhopper nymphs, moth eggs, scales and thrips. They also can attack other insects including caterpillars. They are available in the form of eggs from commercial insectaries and will stay in a larval stage after they hatch for one to three weeks. The adult insects can fly and will feed only on pollen, honey and nectar to reproduce. Repeated application may be necessary and the eggs could be eaten before they hatch by their natural predators, such as ants or mature green lacewings.
    Ladybirds are also used. They eat mostly insect eggs, but will also feed on beetle larvae, aphids, scale insects and young caterpillars. Adults are often collected when in a dormant state in the wild and shipped for use in pest control, however, they may not stay in the location where they are released. They do live for about a year and will continuously lay eggs and reproduce. Spraying the bug's wings with a sticky substance before release may hinder their ability to fly.
    Another natural way of dealing with whitefly is to grow Nasturtium (anti-feedant) close to i.e. goosberries or tomatoes. It will provide root chemicals that deter whitefly.