We want to know if gnats are attracted to mold, and why?  Gnats are often referred to as fruit flies, phorid flies, drain flies, and fungus gnats.   But regardless of what you call them, they always seem to be flying around your garden or kitchen, seemingly out of nowhere.

In this article, we’ll be answering all the important questions you may have about gnats. How do you get gnats? Are gnats attracted to mold? And, most importantly, how do you get rid of these pesky insects?

Let’s start with the most basic question: where exactly do gnats come from?


Where Do Gnats Come From?


Gnats are unbelievably prolific with regards to reproducing. These insects will often rapidly increase in numbers over a relatively short period of time, especially if not dealt with immediately.

Female gnats lay their eggs in areas with moist soil or with aquatic vegetation. Once hatched, the young larvae will feed on organic matter such as rotting leaves, damp mulch, compost, decaying matter, and fungi, to name a few.

These eggs hatch in 4 to 6 days, and feed for 1-2 weeks at most. Female gnats can lay 100-300 eggs throughout their entire lifespan, and normally don’t live longer than 4 weeks.

These tiny flies will infest wet, humid locations like greenhouses or mushroom farms. They’re also commonly found flying around fruits and vegetables that aren’t stored in sealed containers. Including any food spillage, exposed garbage cans, and mold.


Factors That Contribute to Mold Growth


Mold doesn’t simply just grow anywhere, contrary to popular belief. In order to effectively fight the growth of mold, you’ll need to first understand the source.

Fungal growth is supported by four factors.


Every species of mold requires a damp environment to grow and foster. Without water, it’s almost impossible for mold to grow.


Just like every other living creature, mold needs nutrients to grow. Most commonly it requires high-sugar or high-salt, which are often found in organic materials.

Examples of organic materials include wood and paper. Also, the remains of other organisms such as fruits, vegetables, plants, animals, and their waste products.


The most ideal growth temperature of molds is between 60 – 90°F, with approximately 70% relative humidity. That being said, there are other types of mold that absolutely thrive in high temperatures of above 115°F. This is why mold often grows aplenty in the Summer season.


In chemistry, pH is a scale that is used to specify the acidity of an aqueous solution, usually measured on a scale of 0 to 14. Room temperature water has a pH level of 7. Acidic solutions normally have a lower pH level than water, whereas alkaline solutions have a pH higher than 7.

Most mold requires a slightly acidic environment to flourish. The ideal level for molds is a pH range of 3-7.


The Link Between Gnats and Mold: 3 Reasons Why Gnats Are Attracted to Mold


If there is mold, gnats often follow closeby. But why?


They Both Grow in Humid Environments


Mold, just like gnat larvae, grow on almost any substance where moisture is present. Both are also often found in cellulose-based building materials. This means that the more moisture you have, the more gnats you’re likely to find.

To name a few, plywood, drywall, composite wood flooring, and carpet padding are all considered food sources for molds.


Gnats Feast on the Decomposition of Molds


Laying eggs in places where there’s an abundance of mold makes its growth increasingly favorable.

This is especially true as these little creatures sustain themselves on the decomposition of mold. Wet, moldy paper is easy for gnats to eat, as well as other damp, moldy household materials.

Some gnats even feed on soap scum and mildew that are found in bathrooms. Due to the warmth and moisture that comes from the shower, bathrooms are considered one of the biggest breeding grounds for mold

Gnats Are Attracted to the Smell of Molds


Gnats are attracted to the smells molds emanate.

Molds secrete gasses called Microbial Volatile Organic Compounds (MVOCs), which are what give mold its unique musty odor, similar to the scent of wet socks or rotten wood.

For many homeowners, the smell is considered unpleasantly pungent. If you notice a sudden increase of gnats, chances are that they’re attracted to the mold growing in your house.


Other Bugs That Mold Attracts Besides Gnats


Gnats aren’t the only insects that favor living close to moldy enclosures. This isn’t because insects eat the mold itself, no. It’s primarily due to the fact that they feast on its byproduct. Here are the top 5 common house pests that mold attracts.


Cockroaches feast on practically anything, including paper. Mold breaks down organic material, which makes feasting on paper and softwood so much easier for cockroaches.


Booklice, as its name suggests, consume the paper found in moldy books. You’ll also find these pesky critters behind wallpapers, old magazines, and around windows.

Mold Mites

Mold mites are the cousins of dust mites, who thrive off of the mold. These tiny, white bugs are commonly found in soil, homes, and rotting buildings, and have been documented to feed on fungi, molds, and yeast.


Mold and termites have a give-and-take relationship. Mold helps break down wood to make it easily penetrable for termites. Termites create tiny tunnels in the wood, which allows mold to reach a bigger surface area inside the wood.

Another reason why termites are so drawn to mold is due to the mycotoxins produced by most fungi. This makes wood infected by mold such as more appetizing.


Beetles, more notably the foreign grain beetle, is another insect that lives off of molds. They’re commonly found in homes with high levels of humidity and in homes with wet lumber and building materials.


What Else Are Gnats Attracted To Besides Mold?


In a nutshell, gnats are attracted to three things:

  • Moisture
  • Scent
  • Organic Matter

Depending on the species, gnats can be found in a number of places. Here are a few places where you can find them, whether it’s inside or out of your home.


Outside Your Home


Your yard can be a gnat’s dream come true. Vegetable gardens, fruit trees, and flower beds entice a variety of gnats as it’s a great source of food and moisture. Gnats are likewise attracted to the mold that grows when one over-waters their lawn or flowerbeds.

In addition to this, many species of gnats are attracted to outdoor lighting in one’s yard.

Here are where gnats are commonly found outside your home:

  • Drain, sewers, and septic tanks
  • Soil contaminated with sewage
  • Rotting fruits and vegetables
  • Damp organic materials found in garbage heaps
  • Trash found outside such as empty soda cans, beer bottles, vinegar, etc


Inside Your Home


Many of what attracts gnats outside your home would also attract them inside.

  • Soil of overwatered potted plants
  • Overripe fruits and vegetables
  • Uncovered drains
  • Left out food on the table
  • Decaying organic matter found in garbage cans and sink drains


Getting Rid of Gnats and Mold


Household mold and insect infestations should be dealt with as soon as possible. Both quickly spread uncontrollably throughout one’s home. It’s worth noting that they may cause a serious problem when left untreated.

Here are some tips on how to get rid of gnats inside your home once and for all.


Step 1: Identify the Pest

There are four common types of gnats: fruit flies, drain flies, phorid flies, and fungus gnats.

Fruit flies are brown with red eyes, typically round in shape. These gnats are commonly found in the kitchen  feasting on food that’s left out on the table.

Drain flies have moth-like wings and have a fuzzy body. As its name implies, it’s commonly found in drains, sewers, and septic tanks.

Phorid flies look a lot like fruit flies but have black eyes instead of red. These insects are attracted to garbage, drains, and rotting vegetables and fruit.

Fungus gnats are black with long legs. They’re found in decaying organic matter in moist soil and overwatered potted plants.


Step 2: Eliminate Its Breeding Ground (Mold)

Mold and gnats grow in damp areas, so you’ll need to find out where this moisture comes from. It may come from plumbing leaks, ventilation or drainage issues, peeling paint, rotted window sills, wet or rotting sheathing, etc.

Often, these issues can be taken care of without the need of a professional, but it’s definitely a good idea to call for one if leaking persists.


Step 3: Eliminate Food Sources

This is best done by cleaning your kitchen, throwing rotting fruits and vegetables, sealing your drain, replacing old wood, covering your trash cans, and avoiding over-watering your potting soil.


Step 4: Use a Bit of Force To Get Rid Of Gnats

By this, I mean using products that aid in killing gnats.

Such products are as follows:


For a more natural solution, you can always use apple cider vinegar traps to kill fruit flies. Here’s how to make it:

  1. Pour apple cider vinegar into a glass or remove the cap from a bottle
  2. Cover the opening with a plastic wrap
  3. Secure with a rubber band
  4. Poke small holes with a toothpick for fruit flies to enter


Final Thoughts


Are gnats attracted to mold? Yes, they are.

Gnats and mold will most likely disappear once you follow the steps mentioned above. However, if you’re facing a severe infestation, do call a pest control professional to exterminate these gnats.