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Diatomaceous Earth For Fungus Gnats

Fungus Gnats on Plants

Controlling fungus gnat problem is important as fungus gnats not only feed on the plant but also feed on the roots and root hairs in the soil.  Although, they are weak fliers, in numbers they can do lots of damage to even indoor plants in a short period of time.  Fungus gnats are commonly found in greenhouse operations, potted house plants, varieties of potted plants, and outdoor gardens where its moist and humid.  Luckily, we give some great tips on fungus gnat pest control.  Lets find out about diatomaceous earth for fungus gnats.

How to Identify a Fungus Gnat

Fungus Gnat

Fungus Gnats resemble mosquitos with long legs that are dark in color when adults.  Fungus Gnats increase in population around the warmer seasons as they are born in the potting soil purchased by consumers.  Adults fungus gnats have wings that are in a Y-shape.  They tend to hop when on soil or on plants as they are weak fliers.  Fungus gnat larvae are 8mm in length and are transparent with a tell tale shiny black head on them.  Best way to know for sure if you have fungus gnats is to set up sticky traps that you can find here at arbico organics.

Life Cycle & Behavior of Fungus Gnats

Fungus Gnat Life Cycle

The Life Cycle and behavior of fungus gnats comes down to 4 parts.  These parts start as an egg, larvae, pupa, and finally the adult.  Please note, all these stages of a fungus gnat love moist soil.  The larvae does the majority of the damage as they stay under the soil to feed on fungi, roots, and root hairs.  This causes a systemic reaction with the potted plant and with dwindle its health.  Each part of the life cycle is only a few days so it is common to have a fungus gnat infestation with all 4 stages of life.  Adult gnats will lay eggs on the sub surface of the soil mix.  These eggs hatch and the larvae come out to feed on the roots of your plant.  From there the pupa emerges and continues to feed.  Finally the adult comes out of the soil surface to mate and feed on soft plant tissue.

How to Use Diatomaceous Earth to Kill Fungus Gnats

Before we learn how to use food grade diatomaceous earth to kill fungus gnats we first need to understand that fungus gnats are little more pesky than common garden insects.  Fungus gnats primarily cause damage to the root zone and root hairs of your plant, where organic matter is high.  We want to kill fungus gnat larvae and the pupae.  This solution also helps to combat adult fungus gnats as well before they can reach the top of the soil to lay eggs.  Below we have provided instructions on how to combat fungus gnats indoors.  Now, Lets get down to brass tax.

Step 1:  The very first thing to do when combating fungus gnats is clean up dead leaf material and also any standing water.  Whether you have a tent and are growing plants or houseplants...chances are there is some standing water around. 

Step 2:  Gather 3% hydrogen peroxide, gloves, water, sticky traps, and diatomaceous earth.

Step 3:  Made a solution of 1 part hydrogen peroxide to 3 parts of water.  Add 3 Tablespoons of Diatomaceous earth de to the solution.  We want you to make this mixture with 2 cups of liquid.  We are kind of killing two birds with one stone here.  On one side the hydrogen peroxide will help to eliminate the fungi, mold, and moist environment in the soil.  On the other hand you are adding diatomaceous earth to the soil.  Diatomaceous earth helps to space out compacted soil and help the roots breathe better.  When we kill the food source of the larvae stage of the fungus gnat, they will be cutoff and die.  When applying the solution, be sure to water slowly and just up to the point where you get runoff at the bottom of the pot.

Step 4:  Let the soil dry for a day and then apply a thin layer of dry diatomaceous earth over the top layer of the soil.  Doing this will kill any adult fungus gnats that want to emerge out of the soil.  We want to be sure that if the hydrogen peroxide and diatomaceous earth drench did not get them all, the application of dry diatomaceous earth will ensure a total kill.

Step 5:  Lightly and just visibly, apply dry diatomaceous earth to the plant itself making sure to get the undersides and topsides of the leaves of the plant.  You may

Step 6:  Apply the sticky traps to the area around your plant to catch any adult fungus gnats before they can mate.  These come in handy.  Make a mixture of 1 part food grade apple cider vinegar and a few drops of dish soap to a bowl.  Really you only need a couple inches inside the bowl.  The fungus gnats we be attracted to the sugar mixture and fly into it.  Once they do that, the ACV and dish soap will prevent them from moving properly and they will die off.

Step 7:  Repeat steps 1-6 until the problem has been solved.  In most cases, a fungus gnat infestation is eliminated after a weeks worth of time.  After a few days you will notice the population dwindling significantly.  Results really depend on the severity of the infestation.  The process may take a week longer if it is really bad.  Use all materials as instructed and remember to keep your growing area clean and free of standing water to help prevent further problems.

*This product can be used in conjunction with neem oil.  Be sure to follow all manufacturer instructions when using neem oil.

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