Mealybugs are small measuring between 1-3mm long and are covered with a powdery wax coating which they use as defense. They are sap-sucking insects and have specialize mouth parts to cut into plant tissue.
Symptoms and Damage:
Similar to scale and other sap-suckers with symptoms being leaf disfigurement, wilting, leaf drop and plant death. Like aphids the mealybug secretes a waste product called honeydew which attracts ants and promotes the growth of sooty black mold. The insects themselves are noticeable because of their woolly coating.
Habitat and Life Cycle:
Mealybugs prefer warm and moist areas and normally congregate at the base of a plant or near new growth which is their favorite food.
Only the females feed on plants with the males serving only to fertilize the female. A single female can lay between 500-1000 eggs in her lifetime and can do so very quickly. Commonly found on cacti and succulents.
Most mealy bug species produce a sort of cocoon for their eggs which resemble a fluffy wool-like ball which make spotting them easy.
Prevention and Control of Mealybugs
There are many benefits to avoiding chemicals when dealing with insect invaders. The harsh chemicals in some insecticides may cause more harm to an already injured plant not to mention the possible harmful effects to you or your loved ones.
✔– First choices for attempting insect control.
✔– Used when green don't solve the issue.
✔– Only use when blue options have failed and the plant cannot be discarded.
Prevention✔- Mealybugs prefer a nitrogen rich environment so proper fertilization and watering help. Keep long weeds, grasses or other plants trimmed around house windows that have house plants in them. Carefully inspect all potential new house plants before bringing them home, this includes the leaves, soil and stems. Regular misting and inspection of susceptible house plants is the best prevention.
Manual✔- If the infestation is small you can pick the mealybug off with tweezers or just remove the infested section entirely. Rubbing alcohol on a cotton swab dabbed on mealybugs kills them instantly but try not to touch the plant.
Organic✔- Tomato Leaf Spray, Garlic Oil Spray, or Neem Oil Spray offer terrific results. Just remember to test which ever you choose to use on a small area of the plant first to be sure it doesn't cause any damage.
Biological✔- Although many effective predators to the mealybug exist none are practical to the house plant gardener.
Chemical✔- Many chemical spray and systemics are available for purchase to control mealybugs. A Google search will help guide you to what is available in your area.
More information on Mealy Bugs:
Wikipedia - http://en.wikipedia.org/wiki/Mealybug
How to control Mealybugs - http://houseplants.about.com/od/pests/a/Mealybugs.htm
University of Manitoba - http://umanitoba.ca/afs/mealybugs.html