Lawn gnats have a knack for invading outdoor get-togethers like uninvited gatecrashers. These tiny, flying insects can quickly become a nuisance. Learn how to get rid of lawn gnats effectively, including how to eliminate breeding sites and natural solutions so you can restore the comfort of your outdoor space.
What do lawn gnats look like?
Lawn gnats, also known as fungus gnats, are tiny flying insects, only measuring ⅛ to ¼ inch. They have slender bodies and six long legs and are typically black or dark gray. Most often, fungus gnats resemble mosquitoes. Their most prominent features are their long, slender wings and thready antennae.
The two most common lawn gnats in the U.S. are Badysia coprophila and Bradysia impatiens.
How do lawn gnats behave?
Effective gnat control interrupts their life cycle, and preventing gnat breeding is the best place to start. Gnats have distinct habits and characteristics, such as:
Feeding behaviors: Gnats feed on decomposing organic matter like compost piles, nectar, and pollen.
Landscape implications: While adult gnats are a nuisance, it is the gnat larvae who do the most damage to unsuspecting landscapes. Gnats multiply quickly, and their larvae damage plants and grass. They also have the potential to spread disease and kill infested plants if left untreated.
Lifecycle: First, fungus gnats lay eggs in moist soil. Larvae hatch and feed on organic material, fungi, and plant roots before becoming pupae. Lastly, adult gnats emerge.
How to get rid of gnats
Minimize the annoyance and health risks of lawn gnats with various control methods.
Remove breeding sites
As long as you have rich, moist soil for the tiny insects to lay their eggs, lawn gnats won’t want to leave. One of the most effective ways to reduce gnat populations in your yard is to eliminate their breeding sites. Here’s how:
- Reduce overwatering: Overwatered turfgrass and landscape plants create breeding grounds. Allow the top inch of soil to dry out between waterings and only water when necessary.
- Clean up debris: Fallen leaves, grass clippings, and other organic debris create moisture on your lawn and serve as a food source for fungus gnat larvae.
- Dispose of infested plants: Remove and dispose of plants infested with gnats to prevent the infestation from spreading.
- Address drainage issues: Improve the drainage of your landscape and prevent water from pooling to reduce attractive areas.
- Avoid over-fertilization: Excessive plant growth creates excess organic debris for gnats to feed on. Always use fertilizers as directed.
- Mulch wisely: Gnats love mulch. Always use a moderate layer of mulch and never pile it against plant stems.
Pro tip: Gnats love to swarm puddles, pools, birdbaths, and other sources of standing water. Maintain proper chemical levels in your pool and regularly replace the water in any water features to control the pests.
Use natural gnat control
Natural control methods can be both eco-friendly and effective. There are several strategies to naturally reduce gnats in your landscape, including:
Repel gnats with herbs
Plant herbs in your landscape. The natural compounds and scents repel gnats (bonus points for their culinary uses). Gnat-repelling herbs include:
- Basil
- Catnip
- Chives
- Lavender
- Lemongrass
- Mint
- Rosemary
Pro tip: Many of these plants do double duty as mosquito, flea, and tick repellent, too.
Attract natural predators
Attract natural predators to your yard and let nature take its course. Not only does this create a balanced ecosystem, but it also reduces gnat populations. Gnat predators include:
- Bats
- Birds (Swallows, bluebirds, and chickadees)
- Hoverflies
- Ladybugs
- Ground Beetles
- Nematodes
Minimize artificial light
Artificial lighting affects gnat behavior, especially during the evening when you are enjoying your outdoor patio. Gnats are drawn to light sources. However, replacing your standard white light bulbs with yellow or amber bulbs reduces gnat attraction.
Apply pesticides
Chemical treatments are an effective solution for persistent gnat infestations. They offer rapid relief, targeting and eliminating gnats in various stages of their life cycle. Consider the following chemical control methods:
- Broad-spectrum insecticides: Apply pyrethrin sprays or granules in affected areas. Broad-spectrum insecticides target a range of insects, including gnats.
- Foggers: Also known as bug bombs, these deterrents release a mist of insecticide in a confined area. They are best used for indoor gnat control.
- Larvicides: Larvicides target gnat larvae, disrupting their development and preventing them from maturing into adult fungus gnats.
How to use a broad-spectrum insecticide
To minimize the negative effects, only apply insecticide to infested areas instead of your entire yard. Specifically, target moist areas.
- Mix enough insecticide to cover the infested area. Dilute the insecticide with water according to the manufacturer’s label.
- Apply the insecticide to the areas where gnats are problematic. Focus on plant foliage and soil areas where larvae are present. Ensure even coverage but avoid oversaturation.
Pro tip: Avoid spraying the insecticide directly onto flowering plants or areas where bees or other pollinators are active.
Landscaping for gnat control
Reducing excess moisture in your landscape plays an important role in controlling lawn gnats. Combine some of the following landscape strategies to repel gnats effectively:
- Use well-draining soil: Prevent waterlogged conditions with well-draining soil. Improve drainage by amending the soil with organic matter like compost.
- Install drainage: Install a French drain if your yard is prone to flooding. French drains redirect water away from plant roots eliminating favorable conditions for gnats.
- Mulch mindfully: Mulch has many landscape benefits. However, it also produces a layer of moisture for gnats to hide. Use mulch sparingly if your landscape is prone to these tiny pests or opt for an inorganic variety like rubber mulch.
- Consider raised beds: Raised garden beds reduce moisture accumulation, creating a less attractive environment for gnats and other landscape pests.
- Maintain your landscape: Keep your landscape tidy by removing fallen leaves, bagging grass clippings, and eliminating overgrown vegetation. Gnats require organic matter to lay their eggs.
- Aerate the soil: Consider aerating annually to reduce soil compaction and increase drainage. Aeration reduces overly wet conditions favorable for breeding.
Rely on professional pest control
Overwhelming gnat infestations are challenging to manage through DIY methods alone. Consider calling in a professional to manage severe gnat problems and help you eliminate their preferred environments.
Temporary gnat control methods
If you are dealing with a gnat infestation in your garden or home, temporary control methods can help alleviate the issue while you work on long-term control solutions. These methods eliminate and repel gnats in localized areas to make your home and outdoor space more enjoyable. Short-term gnat control methods include:
- Sticky traps: Adhesive traps attract and capture adult gnats. Place them near your plants or areas where you have noticed gnat activity.
- DIY traps: Create a homemade trap with apple cider vinegar and liquid dish soap. Fill a jaw with apple cider vinegar and add a couple of drops of dish soap. Cover the jar with plastic wrap and poke holes in the top for gnats to enter. The vinegar lures the gnats while the dish soap traps them in the liquid solution.
- Neem oil: A homemade neem oil spray deters adult gnats and disrupts their life cycle. Mix water, neem oil, and a few drops of dish soap in a spray bottle. Spray the solution on your affected plants.
- Essential oils: Oils like eucalyptus and lavender have natural gnat-repellent properties. DIY create your own spray by mixing a few drops of oil with water and applying it to affected areas.
- Citronella candles and incense: These products contain scents and produce smoke that lawn gnats find unpleasant. Place the candles or incense around your outdoor seating area to create a protective barrier.
- Outdoor fans: Install outdoor fans on your patio or deck to create a breeze. Gnats are weak fliers and have difficulty in strong currents.
- Bug zapper: UV light attracts insects, and when the insects come in contact with the zapper, they are electrocuted. These devices work best in localized areas and eliminate many flying insects including house flies, mosquitoes, and gnats.
FAQs about getting rid of lawn gnats
When are lawn gnats most active?
Like mosquitoes, gnats are most active during dusk and dawn. They prefer warm, humid conditions, spring, and summer, and are particularly active after watering or rainstorms.
What causes lawn gnats to come indoors?
Houseplants and decomposing fruits or vegetables attract indoor gnats. Fungus gnats can infest an indoor plant or adult gnats can emerge from infested potting soil. Gnats enter your home through open doors or windows, especially during the warmer months.
How do I get rid of indoor gnats?
Eliminate indoor gnats by isolating affected potted plants. Repot houseplants with fresh, well-draining soil and reduce indoor humidity levels if possible. Consider using sticky traps for severe infestations, maintain a tidy home, and eliminate ripe or rotting fruit that attracts gnats.
Are black flies, fruit flies, and drain flies a type of gnat?
No. While they appear similar, black flies, fruit flies, and drain flies are not gnats. Black flies inflict painful bites. You can find them outdoors, especially near freshwater sources like streams or ponds. On the other hand, fruit flies are often mistaken for indoor gnats, preferring fermenting fruit and organic matter while drain flies frequent bathrooms and kitchen sinks.
Get help with your outdoor gnat infestation
Sometimes gnat control requires a complete landscape overhaul which can be overwhelming. If you need your yard’s drainage assessed or aren’t sure which landscape plants will deter insects, let Lawn Love connect you with a local landscaping expert to assist you. However, if you need help eliminating active gnats and other insects in your yard, reach out to Pest Gnome for a tailored solution.
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