Hydrogen peroxide at a concentration of 3% is useful for controlling larvae. Make a solution by combining 1 part hydrogen peroxide with 4 parts water to get rid of fungus gnats.
Only use this solution to water your home plant when the top of the potting soil is completely dry. There may be an effervescent sound as the peroxide solution is poured into the soil.
The peroxide will decompose in the soil once it has finished killing the gnat larvae. Your plant won’t be harmed in the least. Even though it ought to work the first time, you might need to do it again.
What rapidly eradicates fungus gnats?
So your African violets have been invaded by fungus gnats? Let’s now discuss methods for managing both adult flies and fly larvae. Here, we advise using an integrated pest management strategy to cover all your bases and permanently safeguard the inhabitants of your greenhouse and houseplants.
Organic Fungus Gnat Control
Surprisingly, one of my top suggestions for getting rid of these pests is a common household item. You can saturate soil in hydrogen peroxide (the standard topical variety, 3 percent).
Pour a solution of one part hydrogen peroxide to four parts water through the soil in the root zone of the pot until it starts to emerge from the bottom. On contact, fungus gnat larvae are killed by the peroxide.
Neem oil works well as a soil soak to get rid of fungus gnat larvae. Follow the manufacturer’s instructions to dilute the oil with water, then immerse the plant’s roots in the solution. To deter adult gnats, you can additionally spray the plant’s uppermost part.
Neem oil contains concentrated azadirachtin in its natural state. It is safe to use indoors, in greenhouses, gardens, and hydroponically. Use it as directed by the manufacturer, much like you would neem oil.
Sprays containing pyrethrin are also effective at killing fungus gnat larvae. Use pyrethrins by misting the soil’s surface and all plant surfaces with a light mist. A light mist will do; you don’t want the plants to get drenched. Spray the soil exactly where adults usually rest to completely hydrate the top if there are fungus gnat larvae present, then prevent overwatering. Let the soil dry to a depth of at least two. When the issue has passed and the insects are no longer a concern, reapply these after three to four weeks.
Adults and larvae are the targets of a predatory Hypoaspis miles mite. Additionally, it preys on other insects like thrips and springtails, which can be a pest in a greenhouse or garden. Since solitary specimens are more difficult to treat, these are best used outside or in greenhouses.
As you can see, there are numerous biological control treatments available for the removal of fungus gnats. Apply pesticides along with wise cultural habits and effective preventative measures, and you’re good to go!
Cultural Control of Fungus Gnats
Avoid flooding your growing media. These insects thrive in the moist growing medium found in houseplants. Do not leave standing water in saucers next to growing medium or below houseplants for an extended period of time. Keep your growth medium away from your potted greenhouse residents and fix any irrigation system leaks that develop. To get rid of any larvae that may be feasting on the organic elements in your compost, pasteurize the growing medium. If you don’t like the notion of doing it yourself, use heated commercial growing medium mixtures. While you take care of the issue, keep any sick plant material and growth medium away from other people.
Biological Removal of Fungus Gnats
Fungus gnat larvae can be killed by a specific strain of bacteria called Bacillus thuringiensis var. israelensis. Most commercial BT sprays do not contain these bacteria, although they are also present as active components in some commercial products. You should see a reduction in your fungus gnat issues if you use them to fertilize your growth media.
By scattering Mosquito Bits or Mosquito Dunks over the soil’s surface and soaking them in, you can also introduce this bacterium. These are suitable for usage both inside and outside. They aren’t just used to kill mosquitoes! As they decompose, Bacillus thuringiensis var. israelensis is released into your soil, where it can begin to kill larvae. Mosquito dunks are more substantial and take longer to work.
The eradication of the fungus gnat larvae might also be greatly aided by the species of beneficial nematodes. The fungus gnat larvae and many other soil-dwelling pests will be eliminated by these microscopic soil dwellers, which you cannot see. Use a pot popper to incorporate these nematodes into the soil when treating an indoor plant. Commercial formulations can cover a larger garden or the entire yard since they uniformly distribute the nematodes with water.
Be warned that using a hydrogen peroxide soil drench and helpful nematodes at the same time will kill the nematodes! Nematodes should not be added back into the soil for at least a few weeks following the infestation. Nematodes should be used in cooler weather if you’re working outside because heat will kill them before they can perform their job. Keep in mind that you must apply more than once, twice a year.
How can fungus gnats be eliminated without endangering indoor plants?
Size: Fungus gnat adults are very little. They are around the same size as a fruit fly, measuring between 1.5 to 3 mm, or 1/16 to 1/8 of an inch. Larvae of fungus gnats can grow to a length of 1/8 of an inch.
Fungus gnats have wings that are either gray or transparent and are an adult grayish-black color. Despite being much, much smaller in size, they have the appearance of mosquitoes due to their lengthy legs and antennas. Fungus gnats are smaller than fruit flies and have larger legs and antennae.
Activity: Fungus gnats often spend the most of their time buzzing about the outside of potted plants’ soil surfaces or close to their drainage holes. They have a propensity to wander along the ground and only soar briefly because they are not good flyers. They fly more like mosquitoes than fruit flies due to their irregular flight and sluggish speed.
Fungus gnats are absolutely harmless, but annoyingly, they frequently fly into people’s faces and beverages. A few well-placed swats will quickly teach them a lesson.
Fungus Gnat Damage
Fungus gnats are more of a nuisance when they are few in number. In actuality, neither plants nor people are actively harmed by adult gnats. However, if their population becomes out of control, the larvae may begin eating plant roots and cause significant harm. This is particularly harmful to young plants like seedlings because they have few, sensitive roots. The plant disease that causes damping down and the eventual death of seedlings can also be carried by fungus gnats.
Damage from fungus gnats will resemble any other root-related problem, such as root rot. Lower leaves may drop and turn yellow, and the plant’s growth may slacken or cease entirely. In really terrible situations, the entire plant may begin to wilt, and if the roots are severely harmed, the plant may then pass away.
How to Get Rid of Fungus Gnats
The key to controlling fungus gnats is to be consistent. The adults are pretty simple to catch in gnat traps, but since the adult population arrives in cycles, you must make sure that your traps are refilled frequently. Use a mix of the traps indicated here and the additional preventative measures listed in the next section for the best results.
Traps with sticky cards: These traps feature a yellow note card that is adhered with a sticky substance. They work best when they are either fastened to skewers just above the soil or chopped into little squares and positioned directly on top of the soil. On the card, adult gnats will fly or crawl and become stuck in the glue. Use yellow sticky cards instead of blue ones since fungus gnats are drawn to that color. Both can be purchased online as well as at the majority of hardware or garden stores.
Simple and efficient, cider-vinegar traps are made of a shallow container filled with water, liquid dish detergent, and a little bit of apple cider vinegar.
- Making a vinegar-and-cider trap Look for a shallow container. Use a tuna can and fill it halfway with apple cider vinegar and water. (The liquid must be at least one-fourth of an inch deep.) Then, gently stir in a few drops of liquid dish soap to the mixture. Placing the trap inside the container on top of the soil or, ideally, close to the damaged plant’s base will work best. Every few days, check it and replenish with fresh vinegar and water.
Flypaper can also be used to catch fungus gnats. Flypaper ribbons are commonly used to catch outdoor flies in horse barns. However, these traps are frequently overkill for gnats and easily stick to items like furniture, hair, plants, and other surfaces that you don’t want them to.
How to Prevent Fungus Gnats
For best success, combine these preventative measures with the aforementioned traps.
Maintain dry soil: Fungus gnats prefer damp soil, so letting your houseplants air out a little between waterings will help to slow down or halt an infestation. Prior to watering again, wait until the top inch or two of soil have dried up. Also, attempt to let as much time pass without watering. If the dirt is dry on the surface, gnats may not lay their eggs.
Use mosquito dunks (containing helpful bacteria) to prevent mosquito larvae from overcrowding fish ponds, fountains, and other small bodies of water. A dry pellet containing the microorganisms Bacillus thuringiensis subspecies isrealensis makes up the product. The larvae of flying insects, such as mosquitoes, fruit flies, and fungus gnats, are infected by and killed by this advantageous bacteria.
- How to apply mosquito dunks Add a mosquito dip to a gallon jug (or watering can) after filling it with clean water. Before dropping the dunk into the water, it’s a good idea to break it up a bit. Alternatively, you can wait for it to soften before doing so. The dunk should be submerged in the water for as long as possible (at least overnight), after which it should be removed (the dunk can be reused) and the water utilized for plants with fungus gnat infestations. Any larvae that come into touch with the bacteria in the soil will be infected and killed because the infection has already gotten into the water. For at least a few months, repeat this procedure each time you water your plants.
Cover drainage holes: Gnats frequently stay near the tops of pots, but occasionally they will make their way to the drainage holes on the underside and begin laying eggs there as well. If this occurs, cover the drainage holes with a piece of synthetic fabric to keep gnats away while still allowing water to flow freely through. Use tape or rubber bands to secure.
Sand-cover exposed soil: According to some people, fungus gnats can’t reach exposed soil to deposit their eggs if it is covered with a layer of sand that is at least 3/4 inches deep. If combined with the other preventative techniques mentioned above, notably plugging drainage holes, this can be a powerful deterrent.
Do you have any advice for halting or preventing infestations of fungus gnats? Tell us in the remarks section below!
Where can I find gnat-free potting soil?
If you have a lot of indoor plants, it might be challenging to get rid of fungus gnats. The adults can effortlessly fly or leap from one plant to another, depositing their eggs in any location with moist soil.
The adult fungus gnats have a short lifespan, similar to fruit flies. Therefore, your fungus gnat problem will be solved once all the larvae have died.
Fungus gnats can be readily controlled without the use of dangerous synthetic pesticides by adopting natural pest control solutions and techniques. The greatest ways to get rid of those pesky flying gnats from your indoor plants are listed below.
Control soil moisture
Therefore, avoiding overwatering your plants is the simplest and most efficient way to control plant gnats and ultimately get rid of fungus gnats.
On most indoor plants, though, you don’t want to let the soil entirely dry up. To keep the ideal moisture level for your houseplants and get rid of gnats in plant soil, use a soil moisture sensor.
Indoor plant watering tools also make it simpler to water houseplants and aid in preventing overwatering, which will help you get rid of plant gnats.
Water plants from the bottom
When you water plants from the top, the top inch of the soil, where fungus gnat larvae typically dwell, tends to stay rather damp.
Without endangering the plant’s general health, bottom watering plants will make it simpler to maintain drier top soil.
Simply pour water into the plant’s drip tray or storage pot to water it from the bottom, and the plant will absorb the liquid through the drainage holes.
Never let your plant sit in water for an extended period of time. After soaking for around 30 minutes, drain out any extra water.
Use yellow houseplant sticky stakes
A very safe technique of pest control is to place a yellow sticky trap next to the plant. This will draw and catch the adult fungus gnats.
This will only work to control the adult population; it won’t address the root cause of the issue (the larvae).
However, yellow sticky traps unquestionably assist in preventing adult fungus gnats from flying to other plants.
Apply organic pest control products
To get rid of gnats in potted plants, pour or spritz an organic insecticidal soap or a neem oil mixture into the top of the soil.
I mix 1 tsp of mild liquid soap with 1 liter of water to produce my own insecticidal soap.
Neem oil has a lasting effect that aids in prevention and is excellent at killing pests that attack indoor plants. Neem oil can be purchased here.
After a few applications, these organic gnat pesticides ought to work; just be careful not to overwater your plants.
Drying Out Soil
Overwatering plants is a major cause of infestations. Theoretically, you can keep your plant soil dry and inhospitable to gnats by spacing out your watering sessions.
Remove about 2 cm of soil from the plant. As a result, the larvae and eggs are exposed, hastening the soil’s drying process.
Prior to watering once more, let the soil to dry to a depth of about an inch and a half.
It did lessen the amount of larvae squirming around beneath the dirt, but it didn’t totally solve the issue.
Many plants can’t go for lengthy periods of time without water, so if you start watering normally again, the gnats will just start to reproduce once more.
Cider Traps
Apple cider vinegar is the ideal bait in this practical trap since gnats are drawn to it.
The gnats will now try to crawl through the tiny holes in the cling film, but they won’t be able to do so because of the vinegar, and they will drown in it.
The biggest drawback of this approach is that it only eliminates adult gnats, leaving hundreds of larvae and eggs still present in the soil unharmed.
However, it did kill a fair amount of adult gnats, severely reducing the gnat population’s ability to reproduce and lowering the overall population.
Potato Slices
Slices of potato are an inexpensive way to gauge the extent of the infestation and, incidentally, get rid of some larvae because gnat larvae adore raw potatoes.
Pull out the chunks after waiting 4 to 8 hours. The potato will literally be covered in larvae if the infection is severe.
Only dozens of larvae can be eliminated by each potato slice at once. Because adult gnats can lay 200–300 eggs at a time, it would be impossible to eradicate a severe infestation with only potato pieces.
But it’s great for determining the extent of the gnat population and testing the efficacy of your other strategies.
Chamomile Tea & Cinnamon
Strong natural fungicides like chamomile and cinnamon eliminate the principal food source for gnats, rendering the soil uninhabitable.
Boiling water is used to make one liter of strong chamomile tea. Once the tea has cooled, it is combined with four parts water. As normal, water plants with tea mixture.
Spread cinnamon liberally throughout the soil’s surface for a double dose of fungicidal effects.
The gnat numbers were drastically decreased by the chamomile/cinnamon dousing within days, but the surviving population continued to grow over the following few weeks.