Every fall I bring in several plants from the patio to overwinter as houseplants and most fare well indoors. Except for my terracotta teacup full of succulents. I love the way the burros tail spills over the edge and the senecio stretches like steam. All goes well for those first few weeks in my south-facing window. Until one day, fuzzy critters (aka mealybugs) arrive and I’m forced to deal some death. All. Winter. Long.
Protected by a soft, fuzzy exoskeleton, mealybugs camp out in clusters along the undersides of leaves and reproduce rapidly. A single female lays anywhere from 400-500 eggs in her short life. She dies after egg laying. Piercing-sucking mouthparts enable them to extract nutrients from their host and diminish its vigor. They tend to favor fresh new growth.
A tell-tale sign of their presence is the honeydew they excrete that forms a clear sticky covering on the plant, hindering photosynthesis. Over time, a heavily infested plant will drop leaves or produce stunted growth, become yellow and/or misshapen.
Where Do They Come From?
Despite having cleaned and inspected each plant before bringing them indoors, mealybugs are excellent Houdinis, nestling into the crevices and joints of plant parts only to reappear later. Protected by a fuzzy coating, egg sacks can be tucked into the deeper parts of the plant and go unnoticed until the nymphs emerge. Since they retain their legs throughout their lifecycle, they’re able to move from plant to plant. It’s important to quarantine infested plants until you have a handle on the problem.
How To Eliminate Mealybugs
Mealybug infestations are tough to eradicate, but a few simple steps can help minimize the damage and keep freeloaders in check. Quarantine and regularly inspect all new plants before introducing them to your houseplant collection. Cottony residues and white flecks along leaf ribs are tell-tale giveaways.
There are several methods of treatment once you identify an infestation. How you treat it really just depends on your patience level and the severity of the problem. Sometimes it’s better to chuck the whole plant and start fresh if it’s covered in fuzzies.
- Alcohol and a Q-Tip works great on smaller problems. Simply dip the swab into rubbing alcohol and apply it directly to the mealybug. The alcohol dissolves the exoskeleton and results in death by dehydration. Strangely, I found this method very therapeutic.
- Insecticidal Soap is available at the store but you can make your own for pennies. I use Dr. Bronner’s Peppermint Pure-Castile liquid soap. To a quart-size spray bottle, add 1 teaspoon of castile soap and one quart of tap water. My tap water is softened so I use bottled water for this mixture. Give it a shake and spray it liberally on the plant, being sure to spray the undersides of leaves and stems. Treat once a week for four weeks or until you see improvement.
- Neem Oil is a natural insecticide commonly used on the Indian subcontinent. I’ve used Espoma Organic Neem Oil 3n1 with good results. It’s safe for ornamental and edible crops.
Before spraying any plant, be sure to do a test patch on a small area. Wait a day or two, then check for leaf damage. Some plants are more sensitive than others. If it looks damaged, rinse the plant with fresh water and spray individual mealy bugs with a steady stream of water. This is most effective for light infestations.
How do you deal with houseplant critters?
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