How to keep bugs OUT when you bring your favorite patio plants inside the house this winter
If you'd like to rescue your favorite patio plants from the cold this winter but are worried about bugs, these tips will help keep your house green and bug-free.
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Bringing tropical plants inside for winter is one of the best ways to keep a garden growing year after year, but everyone always asks me, "But what about the bugs!?" You can't completely eliminate every creepy crawly, but you can be pretty close to bug-free.
Start with a bug check
Look closely at the leaves, stems and soil. If a plant isn't healthy, it's probably also overloaded with bugs so only bring the best plants inside. Pay particular attention to the undersides of leaves, where aphids, whiteflies, spider mites and scale can hide. Fungus gnats are unavoidable because they live in moist soil, but I have a tip later in this article that gets rid of them every single time!
Neem oil for the leaves
Sap-sucking insects don't typically venture far into your living space, but they can completely overrun your plants. A simple neem oil spray can help control these soft-bodied insects and other pests on the plant.
I use concentrated neem oil and typically add about two capfuls for every gallon of water. I also add a few drops of mild liquid dish soap and 1 quart of water. Put it in a spray bottle or hand pump sprayer and shake it up before applying!
The neem oil works primarily as an insect growth regulator and feeding deterrent. It can affect pests including aphids, whiteflies, spider mites, mealybugs and some other insects.
The dish soap acts as an emulsifier, helping the oil mix with water instead of floating on the surface. It also helps the spray spread across the leaves and can damage the outer coating of some soft-bodied insects.
A word of caution: This spray is organic and non-toxic for humans and pets; however, it can harm some plants like bromeliads. Test it out on a small part of the plant and wait a day to see if there's any burn on the leaves before you apply it everywhere.
What about fungus gnats?
I struggled with gnats for a long time, but I never see them anymore now that I have a bug zapper. The adults are attracted to the light and can be captured by the device, reducing the number of adults laying eggs in your potting soil.
Never use a bug zapper outside! Outdoor zappers can kill large numbers of beneficial and harmless flying insects, including pollinators and other insects that are part of the local ecosystem. They are much better suited to a controlled indoor environment.
The bigger battle with fungus gnats is in the soil. Letting the surface of the potting mix dry between waterings can make the environment less attractive to them.
Diatomaceous earth: Helpful, but not a cure-all
Diatomaceous earth is a fine powder made from the fossilized remains of microscopic aquatic organisms. It's organic and safe, but do not inhale it because the fine dust is an irritant. For this reason, I would avoid using it near kids or pets and wear an N-95 mask to be on the safe side. When the dust is dry, its abrasive particles can damage the protective outer layer of crawling insects, causing them to lose moisture.
The advantage is that it is a chemical-free mechanical control and can be useful around the surface of dry potting soil and in areas where crawling pests are present. The downside is that it only works when it's dry, so you may need to reapply. Avoid breathing the dust when applying it and follow the product's label directions.
The Winter plant check
Give some thought to what plants are worth bringing inside. If they have sentimental value or are difficult to find, I'll always try to find a space. However, it's usually not worth bringing an already struggling plant inside. If it's not doing well under Mother Nature's care, then it really has an uphill battle to fight inside the house where conditions are much more challenging.
