Mealybugs are tiny, white parasitic insects about 1-2mm long. They gather together in clumps that look like balls of fluff, particularly in the leaf axils (where leaf meets stem) and on the underside of leaves. They suck the sap out of the plant, eventually causing stunted growth or even death.
If you only have a few, dab methylated spirits directly onto the bugs with a cotton bud. If you have an infestation, thoroughly spray the plant all over with neem oil, and repeat in 7 days.
Scale have a smooth oval shape shell that can be white, black, or brown. They also suck the sap from plants and multiply quickly. Spray thoroughly with white oil, to suffocate and kill the scale. The hard outer shells can also remain stuck to plant after the bugs die off so you can lightly wiping down the leaves can also help.
Spider mites are tiny but have couple of tell-tale signs – webbing on the underside of leaves or discolouration along the leaf edges. An entire leaf may die off if the mites take hold. They dislike moisture, so wash down the leaves of your plants and soak the soil to remove both adults and eggs, disrupting their breeding cycle.
Don’t leave the soil damp for too long though, or you’ll leave it vulnerable to fungus gnats!
Fungus gnats are a small, black flying insect that hover around the surface of pots. They are not harmful to the plant, but letting the soil dry out between watering will help reduce their numbers. Alternatively, mix up 1 part peroxide to 4 parts water in a watering can and drench the soil until it’s running out the bottom.
Fungal infections such as rust are common on plants with big leathery leaves like monsteras and philodendrons, identifiable by rusty brown marks on the underside of leaves. Other culprits are those that leave sunken or wet brown patches on the edges of leaves. These can all be treated with organic fungicides to prevent further infections.
The best way to minimise these issues is to stop them coming in the front door in the first place! Choose plants carefully, checking the undersides of leaves and in the crown of the plants where bugs and their tracks are likely to be found. There’s no failsafe way to prevent pests and diseases though, so keep an eye on your plant babies and be ready to defend them!
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