Pests Spotlight: Mealy Bugs
Signs Of Mealy Bug Damage
You may have Mealy Bugs damage if you see the following signs:
Small white bugs on the underside of leaves
White cotton-like clumps
Yellowing and dying leaves
Black, sooty mold on leave surface (mealybugs excrete honeydew that lands on lower leaves or on the ground, and that becomes colonized by sooty mold)
Where To Find Them
Mealy bugs tend to feed at stem tips, where the stems meet the leaves. They usually hide on the underside of leaves and are generally slow moving. The presence of increased ant activity on the plant could also indicate the presence of Mealy Bugs.
Ants farm mealy bugs for for the sticky sap called 'honeydew' that is excreted as the Mealy Bugs feed on the plant.
Conditions that Mealy Bugs Love
Mealybugs prefer mild warm conditions with temperatures around 25°C and high humidity.
Increase inspection on the undersides of leaves especially after consecutive days of rain.
Mealybugs are attracted to plants with high nitrogen levels and soft growth; they may appear if you overwater and over-fertilize your plants. Over fertilization causes plants sap to become sweeter and this results in attracting sucking pests like spider mites and mealy bugs.
Treatment Options
Use Organic Neem Oil Concentrate to combat plant pests and fungus. It is a non-toxic solution that causes insect pests to reduce or cease feeding, prevent larvae from maturing, and reduces or interrupts mating behaviour. Neem oil is a natural product of the Neem Tree, and is effective at killing fungal spores too. Unlike chemical pesticides that have instantaneous results, organic pesticides like Neem work pest when used as a preventive tool and as part of an overall Pest Management Strategy. In treating pest infestations organically, it is important to break the life cycle of pests by preventing any larvae from maturing and also preventing mature pests from feeding. Mealy bugs lay up to 600 eggs in a cottony-mass, and a new generation is formed every one to three months. After laying eggs over a period of 5-10 days, the adult female dies.
Left: mealy bug destroyer; Right: mealy bug
A natural and lesser known remedy is the Mealy Buy Destroyer, a beneficial insect that preys on mealy bugs, aphids and other soft scaled insects. One Mealybug Destroyer larvae can consumer up to 250 mealybug larvae! These beneficial insects are commonly misidentified as they look so much like their prey - the mealy bugs. Their modus operandi is very effective: the adult female lays her eggs in the cottony egg sack of the mealybug. As soon as they hatch, the destroyers start snacking. Adults and young larvae prefer eggs, while older larvae will consume mealybugs at all stages. They will even feed on honeydew, the sticky sugary substance secreted by mealybugs, thus reducing the risks of black sooty mold colonising the leaf surface. Biodiversity is key in attracting these beneficials to your garden. Plant a wide variety of plants, with various heights, shapes, and colors so it creates an inviting environment for beneficial insects like the ladybug and mealy bug destroyers to live in. For Early Stage Infections How You’d Know: Only a few leaves are affected and curling over,only 1 or 2 visible cottony mass with little to no presence of ant activity. What You Can Do:
Prune away affected leaves.
Dilute neem oil solution as directed; spray liberally on both sides of the leaves once every 3 days for 1 week.
Reduce to once every 7 days for 2 weeks.
Continue as a preventive spray once every 2 weeks thereafter.
For Severe Infestations How You’d Know: Yellowing of many leaves, presence of many white cottony mass, presence of bugs on most leafs. What You Can Do:
Give the plant a hard prune and trim away all affected leaves.
Dilute neem oil solution as directed; spray liberally on both sides of the leaves once every 3 days for 2 weeks.
Reduce to once every 7 days for 2 weeks.
Continue as a preventive spray once every 2 weeks thereafter.
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