How Long Do Gnats Live And How To Get Rid Of Them


The average lifespan of a gnat is one week. The temperature has a direct impact on their lifespan because gnats can live a little longer in warmer climates. However, most insects of this size have a lifespan of no more than two weeks.

A gnat lives for about a month, from egg to adult. They only spend about a week or so as fully grown gnats, after which they go through the remainder of their life cycle.

Gnats typically lay their eggs in the soil, both inside and outside. Although they can’t stand extreme heat either, they prefer the warmer environment of your home.

By watering with mosquito bits to kill the larvae and eggs within the soil, you can quickly get rid of gnats. Place yellow sticky traps to catch adult gnats so they can’t reproduce while that’s working.

What Do Gnats Look like?

Many other varieties of small flies found in homes can be mistaken for gnats.

To the untrained eye, fruit flies, drain flies, and phorid flies resemble gnats, but upon closer inspection, gnats are considerably smaller. You can identify the type of fly you have by locating the breeding source. Fruit and vegetable organic matter, food spills, and garbage serve as breeding grounds for fruit flies and phorid flies. Drain flies reproduce in drains, sewer tanks, and sewage-contaminated soil.

In addition to breeding in drains, gnats frequently obtain their food from fungi and potted plants.

Where Are Gnats Coming From

Gnats breed in drains, rotting produce, and trash cans, among other places mentioned above. Fungus gnats are often spotted around potted plants or windows. In very moist soil, they prefer to reproduce. These gnats are tiny flies with long legs and long, thin wings. You can see vein patterns in their wings if you look closely. Their eggs are oval, smooth, semi-transparent, and hardly noticeable. Their maggots (larvae) can grow to be 1/4 inch long, are white, and have shiny blackheads. Their pupae, which resemble silken cocoons, are visible in the soil.

Gnat Inspection

  • Examine the potting soil of plants.
  • Inspect the plants for adult gnats flying around. This gnat swarm could be a sign of breeding soil beneath the plants. Gnat larvae in the soil may be hard to find or see.
  • If there are no planters or atrium areas acting as breeding sources, gnats may be entering the structure from the outside. Examine the vegetation, soil, and organic matter close to entry points such as doors and windows.
  • Keep an eye out for adult fungus gnats flying around the plants outside as well.
  • Sometimes, the building’s exterior lighting may be luring fungus gnats from nearby areas because they are drawn to lights.
  • Additionally, keep an eye out for interior moisture issues like swollen wall coverings, paint that is peeling, water stains, etc. These gnats may be reproducing there if the fungus is present.
  • Moisture frequently adheres to the lumber used to construct houses during new construction. Occasionally, in wall voids that take a while to dry out, surface fungi will develop on wood. Rarely, but in new homes where fungi have grown inside walls, severe fungus gnat infestations have emerged. To check if this is happening, take off the plates from wall outlets and cover much of the opening with tape. In order for the gnats to escape the void, leave a space between the tape pieces to allow air to pass through. There will unavoidably be some gnats that stick to the tape if they are breeding in the walls. If the walls are thought to be potential breeding places, try this on all wall openings in infested rooms.
  • Once the source has been located, keep searching. There will typically be several breeding sources available.

Gnat Life Cycle



A few inches of warm, moist soil are where female fungus gnats lay their eggs. As a result of the pests’ preference for hot climates, heated homes, greenhouses, and garden centers are common places where infestations occur. Normally, gnat eggs hatch after six days.

The typical adult gnat lives for one week and can lay up to 200 eggs during that time. The pests can complete their entire life cycle in as little as 28 days. The short answer to the question of how frequently or quickly gnats reproduce is, therefore: A LOT.


Gnat larvae are legless and have shiny black heads as well as white or clear bodies. Following emergence, they consume decaying matter and plant roots for food. You might see slime trails left by gnat larvae on leaves or in planters if a gnat problem is bad. Although warm temperatures accelerate the insect’s rate of growth, the larval stage only lasts for about two weeks.


Gnats begin to pupate at the conclusion of their larval stage. The soil is where this process mostly takes place and it lasts three to six days. The lifespan of a gnat typically ends here. The pests pupate, then emerge as winged adults and start reproducing.


In general, adult gnats won’t bite and won’t harm your plants. Gnats have a short lifespan, but when they’re in large numbers, they can be quite bothersome. They can annoy visitors at hotels and outdoor dining establishments in addition to houses and greenhouses. Gnat infestations can also be a problem for florists.

Factors Affecting The Lifespan Of A Gnat

The gnat’s life cycle is described above assuming ideal conditions for growth and reproduction. However, this process may be impacted by outside factors.


Gnats are most prevalent during warmer weather spells, which are typically from early spring to late summer and are frequently observed from May to August. The gnat season will last longer in the Western and Southern states, which is influenced by geography.

The duration of a gnat’s life can also be impacted by cold weather. Contrary to popular belief, it can actually lengthen something instead of just making it shorter.

According to science, gnats are protected from freezing conditions that would otherwise cause them to perish by antifreeze proteins. Adult gnats can still reproduce and lay eggs.

However, where they can lay them becomes a problem. Depending on the species, the eggs might never hatch if there is insufficient access to unfrozen water or soil.

Their lifespan can be increased if the ova can be laid and they develop into larvae. They can persist in this wriggling state for a longer time than they could in a pupa, which would otherwise freeze to death in the cold.

Recent research from the Pirbright Institute suggests that gnats’ seasonality is changing as a result of climate change. The primary reproductive period of some species has grown by 40 days. This implies that as the years go by, you’ll probably see more of these creatures.

Access To Food And Water

Sex and food are the two things that gnats are most concerned with.

Sex is usually not an issue as they spend time together. It feels like you’re constantly inside a nightclub.

But there’s a problem with nutrition. They will either perish or move if given insufficient access to food or water.

Gnats eat decaying plant matter, other insects, or plants, depending on the species. Removing the food and water sources of these flying creatures can frequently be an efficient way to lower their population and lifespan if they are a problem in your house or garden.


Alarming findings from research conducted by the Yale School of Forestry and Environmental Studies. It explains that gnat populations have decreased by 72% in some parts of Europe while falling by 40% in the USA.

Scientists attribute this decline to the overuse of pesticides, the prevalence of monoculture, and habitat destruction.

Yes, gnats can be a pain. However, they are also very good pollinators, which are crucial for our food crops.

The next time you consider eliminating your gnat problem, stop and think.

How To Get Rid Of Gnats


Step 1: Locate And Eliminate Breeding Sources

  • Potted Plants or Outside Soil: If you have gnats coming from any potted plants, locate the breeding source by performing a thorough inspection and remove the soil or dry the soil.
  • Drains: Check the drains to see if there are drain flies or gnats coming out. Applying clear tape over the top of the drain with airflow holes is an easy way to quickly determine if they are coming from drains. You can identify the presence of gnats or drain flies by observing how they adhere to the tape as they leave the drain.
  • Fruits, Vegetables,s or Food Spillage: Remove any fruit or vegetable matter that has gone bad. Additionally, check the condensation pan underneath refrigerators.

Step 2: Use Traps, Enzyme Drain Products, Or Bti Products

You can use a fruit fly trap or create your own homemade traps if you have gnats or other small flies that are coming from organic sources.

A. Homemade Traps

  1. Old Fashion Vinegar Trap: Put some dish soap, a teaspoon of sugar, and a little (one to two tablespoons) apple cider vinegar in a jar. The soap will keep them imprisoned and prevent them from flying away, while the cider vinegar will act as an attractant.
  2. Ripened Fruits: That ripe apple or banana should not be thrown away. Fruit that has reached maturity attracts fruit flies and gnats. Put some of that fruit in a bowl and cover it with plastic wrap that has been punctured with tiny holes. The flies will enter the bowl but not be able to exit.
  3. Almost Gone Red Wine: If you have fruit flies or gnats, they might be snagged in the wine that is still in the bottle at the bottom. They won’t be able to escape after they crawl into the bottle.

B. Enzyme Drain Products

  • Gnats in the kitchen may be coming from the drains if you cannot find the source of their breeding (food spills or trash). To check if they are coming out of the drains, cover the holes in the drains with clear tape.
  • Pour in the drains with an enzyme drain product, such as Invade Bio Drain. For coating drain sides, the thick formulation of Invade Bio Drain Treatment contains microbes and pure citrus oil. The Invade Bio Drain Treatment will consume the buildup and scum in drains, getting rid of it and drain odors. Invade Bio Drain Treatment’s oil has a pleasant orange scent.
  • Sadly, bleach will not completely remove the debris that has accumulated in the drains.

C. BTI Products (Bacillus thuringiensis israelensis)

  • Mosquito Bits not only will control mosquito populations but will control Gnats
  • The Fungus Gnat larvae will be killed by BTI (Bacillus thuringiensis israelensis), which is present in mosquito bits. Spread or sprinkle a few granules—a small amount is required—as directed on the label. It will be released into the ground by water and kill the fungi gnat larvae.

Step 3: Use Insecticides Or Fly Lights

  • Gnats Outside: After reducing the soil’s excessive moisture levels to eliminate the breeding sources, apply a residual treatment, such as Bifen IT residual insecticide.
  • For quick knockdown, Pyrethrin Aerosol space sprays like Stryker 54 Contact Aerosol can be used.
  • Using a fly trap like Gardner WS 85 Wall Sconce or Gardner GT-200 Fly Light would help control many types of flies, including the Fungus Gnats
  • Spray a residual treatment, such as Bifen IT residual insecticide, on any outdoor areas that may still retain moisture after removing the breeding sources in the soil. Keep kids and pets away from sprayed surfaces until they have dried, and repeat as necessary.

Frequently Asked Questions

What Makes My House Full Of Gnats?

Infested houseplants or moist soil brought inside your home may be the source of gnat infestations. Hundreds of new baby gnats hatch after the soil becomes gnat-infested and fly around the house. Additionally, fresh flowers, unsealed fruits and vegetables, stagnant dirty water, moist garbage, and uncut flowers all attract gnats.

How Many Years Do Gnats Live, And How Quickly Do They Reproduce?

Gnats can live for up to four weeks, but once they get inside your home, you need to take action quickly because they reproduce quickly. Before she perishes in 7–10 days, a female gnat can produce up to 100–300 eggs at a time, 30 times in total. You do the math!

Gnats’ Lifespan And Rate Of Reproduction Are Both Unknown.

The lifespan of gnats is up to four weeks, but once you notice gnats in your home, you must act quickly because they breed quickly. A female gnat can produce up to 100–300 eggs at a time and can lay eggs up to 30 times before she perishes in 7–10 days. You do the math!

Do Gnats Bite Humans?

Due to their small size and lack of orientation sense, gnats typically just cause annoyance to people and plants. They occasionally try to fly into my eyes and slam into my face by attempting a kamikaze maneuver. One type of gnat, called a sand fly, only bites humans when it is a female. Itchy, tiny red bumps are produced by the bites.

What Odor Do Gnats Detest?

Lemon, lavender and vanilla all repel gnats like the plague. You can make your own natural DIY gnat repellent at home using these three scents. To deter gnats from your home, you can also burn candles scented with these ingredients.

Do Gnats Pass Away In The Winter?

Gnats cannot survive in cold temperatures and prefer a climate of 70 to 80 degrees Fahrenheit. However, if you have your plants inside during the winter time, you might want to resort to the above methods to kill gnats since the temperature inside your home might not be low enough to get rid of gnats