One of the most asked questions from our plant parent customers is, “Where did they come from and how do I get rid of them?" They are referring to the common insects that can invade your collection: aphids, mealybugs, spider mites, fungus gnats and whitefly.
Where do they come from? They generally come in on newly acquired plants and the eggs can live in the soil for months before appearing so it can seem like they came out of nowhere. Frequent inspections of your plants, quick action, isolating an infested plant to limit the spread and removal of badly infested branches are a good start to getting rid of these pests. Here's some more detailed info about who they are and what to do if you find them.
Aphids - tiny yellow, green, brown, or black bumps on the stems, tips and undersides of leaves. Often leave a sticky substance behind.
Mealybugs - Fuzzy white spots or patches on leaves & stems, especially in notches, crevices and hard to reach places.
Whitefly - Very tiny white flying insects that look like dandruff and fly around your plants when disturbed.
Spider mites - fuzzy mats of webbing inside your plant, under leaves, etc. with tiny yellow or brown specks. Leaves will often turn yellow or develop a fine, speckled texture.
Fungus gnats - tiny black flies that do not harm the plant but are a nuisance as they emerge from the plant soil and swarm around your house.
Aphids: Start by blasting the plant with hard spray of water to knock them off. Follow up with a spray of insecticidal soap on all parts of plant and soil. Check plant again every few days and repeat treatment as needed.
Mealybug: A bit harder to treat but the best way is to use rubbing alcohol on a cotton swab and wiping down the leaves. It is also a good idea to slide the plant out of it's pot and check the roots. Check plant every few days and repeat treatment as needed - it may take a few weeks to completely eradicate mealy.
Whitefly: To me, these are the worst pests! They are fast reproducers and are usually not noticed until they have invaded your plant(s) in large numbers. Same as with aphids, a blast of water can knock them off followed by insecticidal soap and repeat every few days until sure they are gone.
Spider mites: These are encouraged by dry warm conditions and dusty plants. Wipe your leaves down when needed and stay on top of watering. Placing a humidifier near your plants or very light misting can discourage them. Spraying spider mites with a miticide is typically recommended if infestation is severe and repeating every few days. Because these pests multiply quickly, this is where you may want to decide to cut your losses if the spray is not working.
Fungus Gnats: These annoying creatures drive everyone nuts! It is highly likely the larvae is in the soil, so you need to adjust your watering. They are attracted to moist soil, so do not water until the top 2 inches of soil is completely dry. There are fungus gnat sprays on the market or you can mix one part of 3% Hydrogen Peroxide with 2 parts water, then use the mixture as a soil drench, making sure it reaches the roots.
Remember, always maintain your plants to keep them healthy, this will make them less susceptible to pests.