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How to Get Rid Of Gnats in a Vegetable Garden

Gnats can be a dratted problem. You stand near your vegetable patch, scratching your head, wondering where these pests came from. And it seems that they’re here to stay.

But that doesn’t have to be the case. There are ways to eradicate your gnat problem.

With these simple and effective methods, you can have a gnat-free garden in no time. Continue reading to find out how to get rid of gnats in a vegetable garden.

First Steps to Take to Get Rid of Gnats in a Vegetable Garden:

1. Homemade Gnat Trap: Sticky Boards

Gnats are highly attracted to the color yellow. So combining a glue-covered board that is painted yellow is a genius trap. 

Hang the sticky trap near your vegetable garden and wait. Soon enough, you’ll probably see several gnats (and other insects) trapped before they can lay any eggs.

2. Gnat Trap Recipe: Lure them with Apple Cider Vinegar

Here’s another trap to catch the adult gnats. This one you can easily make at home. Here are the steps to make the trap:

  • Pour some apple cider vinegar into a container.
  • Cover it with a plastic ziplock bag. You can also use food wrap for covering. 
  • Secure the wrap around the container with a rubber band.
  • Make a few toothpick-sized holes in the covering. This is to allow the gnats to enter.

Once they enter the trap, the gnats will either drown in the sweet-smelling vinegar or will be unable to find the exit to escape. Similarly, you can use rotting fruit to attract gnats. 

Place some rotting fruit in a container and cover it up with food wrap that has holes punched into them. Once they enter the trap, throw out the container along with the gnats. Repeat as often as needed.

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3. How To Get Rid of Gnats in Soil? Answer: Alter Your Watering Habits

Gnats, like most garden infesting pests, thrive in moist conditions. So it’s vital that you take care not to overwater your garden. 

Keeping the soil moist-free is key to stopping gnat larvae from growing. Understand how much water your crop needs, and maintain a schedule. You can also invest in a moisture sensor to gauge the dampness level of the soil.

Try all these steps, and you should see a gradual decline in the number of gnats hovering around your vegetable garden.

In addition to the basic steps mentioned, you could also try the following steps to protect your vegetable garden.

Additional Preventive Measures

1. Sterilize the Soil

It is common to see gnat eggs in even freshly purchased soil. Yes, even the new soil you got is likely infested. That’s how pervasive the problem can be. So to counter that, you can sterilize the soil by microwaving it.

Pour the new soil into a plastic bag and place it in the microwave. Set the timer for a minute. After the first 60 seconds are done, take it out, shake the bag and place it inside the microwave. 

Repeat this two more times. Use the soil once it cools down. Please note, do not microwave dry soil; it could cause fires.

2. Unleash Natural Predators

All creatures have predators. Gnats are no different. Their larvae are a food source for certain microscopic critters.

One of them is worm-like creatures called nematodes. These nematodes, when released into the soil, feed on gnat larvae and thus gradually eradicate the larvae populace. 

Similar to the nematodes are killer mites who also live by the same gnat larvae feeding mantra. You can naturally solve the gnat problem by unleashing these predators into your garden’s soil.

3. Pesticides

It’s okay to call in the professionals if things look out of hand. Having a paid pest control service do a job on your garden might allow you to start afresh.

But if you’re still looking for organic pesticides, you could try a water and soap mixture. Spray them directly on the gnats, and they will die. Purchasing neem oil spray can also help. 

Neem oil can effectively kill off pests. But a word of caution, neem oil can potentially harm your plants. Use them when the weather is a bit cool rather than in the heat of the day.

4. Hydrogen Peroxide

A mixture of hydrogen peroxide and water will help tackle your gnat problem. Soaking the soil with the solution will kill the gnat larvae that are lurking near the roots. 

Be sure to mix the water and hydrogen peroxide in a 4:1 ratio (4 parts water, 1 part hydrogen peroxide). It’s a totally safe solution to use. Just avoid pouring any on the leaves.

5. Use Soil Drenching

This is another form of chemical pesticide that can effectively treat gnat infestation in your vegetable garden. Soil drenching is the process of introducing a solution of chemicals and water into the soil, which is absorbed by the roots of the plant. 

The main purpose of such a solution is to allow a microbe called Bacillus Thuringiensis (Bti) to latch on to the roots. This microbe helps fight against gnat larvae and is very effective at it.

You don’t have to use all these steps to fight the gnat infestation. Switch between methods and see which works best.

6. Homemade Gnat Repellent

If you want to stick to the organic route, you can make your own repellents at home. 

Concoct an effective gnat-killing repellent by mixing dishwashing liquid, water, vinegar, and baking soda. Pour the solution into a spray bottle, and you are ready with a DIY repellent. 

Make sure that repellent is made with one tablespoon of vinegar, one tablespoon of baking soda, and a few drops of dishwashing liquid per cup of water. Use it wherever you see gnats appear.

Another killer spray you can make on your own is by adding a teaspoon of dishwashing liquid, a half cup of water, and a cup of isopropyl alcohol. Fill a spray bottle with the solution and spray it directly on the gnats to kill them.

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7. Invest in an Insect Killing Machine

Having a bug zapper near your vegetable garden would do wonders. 

Gnats are attracted to lights. An insect-killing machine is built with exactly the lights that can lure them to their electric mesh. This will work well at night. Adult gnats will be attracted to the only source of light available. 

Hence you could possibly kill them off before they can lay any eggs.


Frequently Asked Questions about How to Get Rid of Gnats in a Vegetable Garden

What kind of damage do gnats cause?

The main culprits are the larvae. Adult gnats are not harmful to plants or us humans. The larvae, though, are known to bore through the roots of your plant, causing it to wither and eventually die. Those plants with deeper roots are sort of immune to the attacks of gnat larvae. However, younger plants face the brunt of all danger since they’re the ones with fledgling roots.

How do I diagnose a gnat problem?

A cursory glance on the topsoil should be enough to spot the larvae. A sure sign of gnat infestation is if you see any of the tiny pests hovering near your produce. If you have soil that is constantly damp, there’s a high chance that gnat larvae are crawling underneath. Also, look for signs of drooping or excessive shedding of leaves. A sign that the roots are under attack.

Where do gnats come from?

Wherever there’s water, there are gnats. Or, it’s moist soil that attracts them. Moist soil is conducive to larvae growth. Hence it’s the perfect spot for gnats to lay their eggs. Also, any decaying matter attracts gnats.

What do gnat larvae look like?

Gnats are generally mistaken for fruit flies. But gnats are actually different in size and color. Gnats look like mosquitoes, with a long abdomen and long legs. They have transparent wings and are really tiny. The female gnat would lay up to 300 eggs in her lifetime. Gnat larvae have white and sometimes transparent bodies. Their head will be a speck of black, and they crawl around on their bellies. After they hatch from their yellowish-white eggs, they spend ten days as a larva before preparing themselves for several days in the pupal stage to metamorphosize into fully grown gnats.

What is the life cycle of a gnat?

Gnats go through four stages in their life cycle. It starts with an egg, then larva, pupa, and lastly, adult.  Once the egg is laid, it takes 3 days to hatch. Once the larva is out, it spends 10 days feeding on roots before developing into a pupa. 4 days later, the adult gnat emerges. An adult gnat can live for up to two weeks. Most of the damage is done during the larva stage.

What seasons do gnats thrive in?

Gnats are generally known to appear in the cool of winter. During the winters, the climate is cooler, and it’s damp most of the time. In places where moist conditions are the norm, gnats will then show up all year long.

Final Thoughts on Getting Rid of Gnats in a Vegetable Garden

Gnats can fatally damage the plants in your vegetable garden. That is if you don’t take care. Fortunately, you can easily notice if you have a gnat problem and seek to address it immediately.

The primary area of neglect is watering. Overwatering is one of the main causes of gnats. They’re attracted to moisture and hence seek out damp soil to lay their eggs. If you can keep the watering in check, have traps set up, and use natural predators, you should be on your way to a gnat-free vegetable garden.

You can use pesticide or a professional pest control service, but as a last resort when it seems that the infestation is beyond your control.

Make sure you keep an eye out for any tell-tale signs of gnat infestation. If you see any of them floating around your vegetable patch, or if you notice almost transparent larvae on the topsoil, then it means you have a problem.

Look for yellowing leaves or drooping foliage too.

By faithfully keeping all the above steps in mind, you can enjoy a clean and safe vegetable garden soon.

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