Watering is a critical part of plant care, and bottom watering can help prevent yucky things like fungus gnats.
To avoid attracting any nasty gnats in the first place, it's best to bottom water your plants. Get a large flat tray, container, bathtub or sink with an inch of filtered or rain water. Place your plants into the water in only their nursery pots. Leave your plants for 15-20 minutes to soak up any water they might need.
Another advantage of bottom-watering your plant is that the top of the soil never gets moist. This dry layer of soil on top helps you to keep insects, fungi, and other pests away from your plant. These pests are all attracted to moisture and thrive in an environment that's humid.
You can try incorporating Mosquito Bits into your waterings which is a natural larvicide that kills the larvae of flying insects – like fungus gnats. The most effective way is to add the bits into your plants' water, letting it soak for 20 minutes which releases the bacterium.
How to Prevent Fungus Gnats. Neither fungus gnats nor their larvae can survive in dry soil, so let your soil dry out completely between watering as often as possible.
Discard the soil immediately, and replace this top layer with sand, which is free of organic matter and dries out quickly—an unappealing medium for fungus-gnat eggs. Let the soil below dry out completely before the next watering.
Eradicate your fungus gnat infestation for good with the following method: Put up a bunch of sticky traps, top-dress the soil with sand and do nematode soaks every 10 to 14 days until the problem is resolved. Also, stop overwatering your plants and eliminate any unnecessary sources of moisture. That's it.
Soil gnats need wet conditions to hatch and reproduce. Ensure your soil is dry before treatment. Water through the soil with a 1:1 mix of water and hydrogen peroxide. The hydrogen peroxide will kill gnats and eggs without hurting the roots of the vast majority of houseplants.
Mix one part of hydrogen peroxide and four parts of water. Use this solution to water your plants. Hydrogen peroxide will kill the gnat larvae and not injure your plant. Keep reapplying weekly until you notice the gnats are gone.
The most common cause of fungus gnats in plants is overwatering, so be sure to let your soil dry out in between waterings as often as possible. Check the soil with your finger every few days, and once you feel it starting to get dry, leave it like that for about a week to keep gnats away. .
Can you over water by bottom watering? Yes, if the plant is sitting in water too long, you can still overwater your plant through bottom watering. However, bottom watering is a more controlled method of watering your plants.
All you need to do is set the potted plant (be sure it has drainage holes) into the bathtub, sink, or another container that's filled with a couple inches of water. After 15 to 20 minutes, the plant will have absorbed the exact amount it needs—never too little or too much.
The general school of thought is that watering from the bottom is the most effective way to water plants in pots. It thoroughly soaks all of the soil, encourages strong root development, and can also help avoid many fungal diseases that come with watering from above.
They're particularly attracted to overwatered gardens and water features like ponds or fountains. Gnats often congregate around unnoticed standing water in the out of the way or underutilized areas of larger commercial buildings like warehouses.
Wet soils, which encourage root rot and fungus, are a breeding ground for gnats. Be careful bringing your tender plants inside to overwinter, as you might be introducing your home to unwanted pests. If left unnoticed and untreated, your plants will begin to show signs of stress.
“These pests are attracted to moisture, so you may see swarms in areas with damp soils, standing water, or even houseplants that have been overwatered,” Ludwiczak adds. “The breeding habits of gnats are most active during warmer months, which is why they seem to be especially prevalent during summer.”
Will fungus gnats go away on their own? Fungus gnats are persistent and will not go away on their own. These pests lay their eggs and multiply quickly, so infestations will continue to grow. The only way to get rid of fungus gnats is to follow a rigorous cleaning program until the infestation has cleared.
The only way to get rid of gnats without killing them is to repel them with scents they don't like: vinegar, vanilla, pine oil, peppermint, lemon, eucalyptus, and lavender. Even dryer sheets could help.
Gnats often infest trash cans, rotten fruit, and other moist places where decomposing organic matter exists. They can also be found near sinks, drains, and toilets.
After about three days, the eggs hatch into larvae, which burrow into the soil to feed on fungi and decaying plant material. Two weeks after that, adult gnats emerge from the soil to repeat the process. Adults live for about one week.
Cinnamon is a powerful natural fungicide, which kills off the gnats' primary food source, therefore making the soil inhospitable. You can also use a cinnamon stick, just pop it straight into the soil. You can grab either cinnamon sticks or powder next time you're doing your supermarket shop.
Miracle-Gro Indoor Potting Soil
Miracle-Gro says this mix doesn't compost or bark, which means you don't have to worry about shelter fungus gnats.
Fast-draining soils with inorganic additives, like perlite, vermiculite, and sand; Inorganic soil covers, like pebbles, coarse sand, chicken grit, or diatomaceous earth (Some swear by the gnat-killing power of diatomaceous earth!); Pyrethrin sprays approved for organic gardening.
Unlike hydrogen peroxide, neem oil solutions kill both larvae and fungus gnats and thereby speed up the process of eliminating the pests for good. To create a neem oil spray, simply mix a teaspoon of dish detergent with a gallon of water and two tablespoons of neem oil.