How Do Gnat Infestations Start? Typically, gnats will enter your house from the outdoors through cracks or holes in your foundation, walls, windows, or doors. Gnats often infest trash cans, rotten fruit, and other moist places where decomposing organic matter exists.

How do gnats form out of nowhere?

Gnats can enter your house from outside, emerge from eggs laid in produce, and grow eggs in potting soil. … Gnats mainly come from eggs laid in unripe fruits. Once the fruit rots, the larvae eat the fruit to grow into adult gnats. Gnats can also enter your home through an open door or window.

Why am I having gnats in my house?

Inside the home, gnats can be attracted to unsealed produce, fresh flowers, houseplants, food spillage and open or overflowing garbage cans. Gnats may also live in sink drains where food residue can collect. Dirty kitchen sink drains can provide food, water, shelter and breeding sites to many fly species.