How to Get Rid of Fungus Gnats on Succulents

Last Updated on June 17, 2020 by Kimberly Crawford

Everything is going great. You have the most beautiful succulents on hand indoors, particularly the gorgeous Aeonium Kiwi and its unique rosettes that look like full-bloomed roses. However, there’s trouble in paradise; bits and pieces of your Kiwi are missing and bitten off by an infestation of fungus gnats!

What are you supposed to do now? How do you get rid of them? What techniques should you employ in order to get rid of the gnat themselves, their eggs, and their larvae without harming your precious succulents?

What are Fungus Gnats?

First off, let’s define what a fungus gnat is. Fungus gnats or sciarid flies are insects that appear every few months. These pests appear seasonally or every few months. They’re like fruit flies in terms of habits and looks. However, the main thing that separates them from each other is that fungus gnats are the bane of the existence of succulents in particular.

Fruit flies are mostly after rotting fruit. These gnats love soaked soil. They hang out around succulents with plant boxes or pots that don’t have well-draining soil most of the time.

Where do Fungus Gnats come from?

An infestation of fungus gnats can occur from anywhere but not necessarily out of nowhere. There are tell-tale signs of why you have a gnat problem, and they mostly root from wet soil that doesn’t drain well or over-watering on your part. Rotting leaves that aren’t cleaned out immediately can also lead to an infestation.

If you have a newly purchased plant and you’re keeping up with its hygiene, it could come from the bag of potting mix you’ve brought indoors or whatever soil you have on hand. The plant itself could have eggs or an unknown infestation as well.

Related: How to water succulents properly

How to identify Fungus Gnats on succulents?

Obviously, if you spot one or more of the insects snacking on your plant then that is a major indicator that it’s been infested. If it’s severely infested, considerable portions of the plant might wilt away and die altogether.

However, even if you don’t see fungus gnats crawling all over the plant, there are still some tell-tale signs that something is amiss in the form of yellowing leaves, poor growth, loss of vigor, and sudden wilting. It might also be a symptom of root rot, sure, but if there are no roots rotting, then the insects might be eating the plant alive instead.

Preventing Fungus Gnats on succulents

As long as there’s decaying plant matter, you will find fungus gnats hanging around. Therefore, one of the many ways of preventing a fungus gnat infestation is to observe plant hygiene and have good watering habits when push comes to shove.

Remember to let the soil dry out completely before the next watering or use soil with better drainage. Also, don’t forget to remove decaying leaves on your pot or garden since these gnats feed on them as well.

5 natural ways to get rid of Fungus Gnats on succulents

#1. Allow Soil to Dry

The best way to kill the larvae and inhibit the development of eggs of fungus gnats is to allow your soil to dry for a depth of 1-2 inches. You should not water your soil until it’s dry. Egg-laying females are less likely to lay their eggs on dry soil as well.

Over-watering the plant, meanwhile, is your best bet in keeping your succulent infested. Fungus gnats develop like fungi in moistness. Speaking of which, excess water on the pot is also bad for your succulents’ health because it induces the rotting of its roots in the first place.

#2. Use Dish Soap Spray

To stop a fungus gnat infestation on your succulent without harming the plant itself, do this. Mix a few drops of dishwasher liquid soap unto a spray bottle full of water then liberally spray the affected plants with your soap water.

Do this daily until the insects don’t show up on your succulents anymore. Sure, you might be concerned about how this keeps your soil moist and makes it ripe for the taking for moisture-loving insects. However, soap water is toxic to insects and will hurt them more than help them.

#3. Put in Cinnamon

Cinnamon isn’t only good for making bread amazingly delicious. It’s also an all-natural method of getting rid of pests and dealing with all sorts of garden issues. It’s like a panacea or cure-all when it comes to dealing with succulent protection.

At the very least, it’s moderately effective pest control. Just sprinkle the cinnamon liberally around the base of the plant on the soil, whether it’s planted on a planter’s box, a plot of land, or on a small pot. Dampen the cinnamon as well to keep the wind from blowing it all away.

#4. Dust with Diatomaceous Earth

Diatomaceous earth (DE) is a substance made up of diatoms. Diatoms, in turn, come in various shapes a la snowflakes. These shapes also include loads of sharp angles. In other words, they’re shards that can do loads of damage if they appear in the wrong place. They can shred up many a fungus gnat to oblivion.

These diatoms are so fine and small they’re capable of puncturing things at the cellular level. This is handy when dealing with bugs, since they’re so small. DE is lethal to bugs because it gets between their exoskeleton joints, thus shredding them up from within.

#5. Introduce Nematodes

You can’t get more natural at controlling pest populations than using nematodes. Nematodes are microscopic roundworms capable of invading fungus gnat larvae in order for them to survive. They’re also good at getting rid of various soil-borne pests like fleas, garden grubs, and so forth.

Meanwhile, they’re safe when in contact with the succulent itself or earthworms that assist in making the soil more arable. They’re also safe on you, your family, your pets, and other plants. Nematodes release bacteria that consume pests like fungus flies from within.

Other pests

Other pests comparable to the fungus fly are the aforementioned fleas, garden grubs, vine weevils, spider mites and mealybugs. Gnats related to the fungus gnats are drain flies or sink flies and fruit flies. Fruit flies appear whenever you have rotting fruit on your table or your garden. Drain flies happen when your drains have issues flushing the sewer water out.