Keeping pests away from your fiddle leaf fig might feel like an endless battle. All houseplants are potential breeding grounds for insects, and fiddles are susceptible to pests like spider mites, mealybugs, and scale. Another insect you might notice bugging your fiddle leaf fig is the fungus gnat. And gnats on your fiddle leaf fig will bug you too!
These tiny flying insects buzz around the leaves of your fig (and around your home!) and lay their eggs in the soil.
Adult fungus gnats aren’t dangerous on their own, but they sure are annoying!
The problem is that gnats lay their eggs in your fiddle’s soil so the larvae can snack on the roots when they hatch, which can eventually cause yellowing leaves. They can also spread diseases to your plants if they get out of control, so it’s best to get rid of them before they spread.
Fungus gnats are tiny, and it’s easy to mistake them for fruit flies. They’re attracted to damp potting soil, so you can find them buzzing around the base of the plant.
Quick Tips for Preventing Fungus Gnats on Your Fiddle Leaf Fig
The measures you’d take to prevent fungus gnats can help you prevent any insect infestation, so they’re worth repeating!
First, inspect any plant you’re thinking of purchasing.
To specifically check for fungus gnats, use your finger to poke around in the top inch of the soil or so. If you turn a section of the soil and notice any wiggly little larvae or adult gnats, don’t buy that plant. You may also want to check out a different store because if one plant is infects, others may be as well!
Next, quarantine new plants.
Insects can easily spread to your other houseplants, so it’s a good idea to keep a new plant separate from your existing plants for a few days or even weeks so any problems can manifest and be dealt with.
When you pot your fiddle, only use fresh soil and clean pots. Insect eggs and larvae can stick around on dirty pots and in old soil. If you have any doubts about soil, discard it and get a new bag.
Avoid over-watering and give your plant lots of light.
Many insects, including fungus gnats, are attracted to dark, damp conditions. Only water when the top few inches of soil are dry (use a moisture meter like this one to be accurate!) and make sure your plant gets lots of indirect sunlight.
Also, make sure that your pot and soil drain well. Fungus gnats LOVE soil that holds onto moisture, so stick with cactus soil or a 50/50 mix of cactus soil and indoor potting mix. Avoid peaty mixes or compost. (We recommend our Premium Fiddle Leaf Fig Potting Soil.)
Read our Ultimate Watering Guide for watering your fiddle leaf fig here.
How to Get Rid of Fungus Gnats on Your Fiddle Leaf Fig
If you’ve already got fungus gnats, here are our favorite tips for giving them the old heave-ho.
Remove the top few inches of soil
Try scooping out the top few inches of soil and replacing with fresh potting mix to get rid of any eggs or larvae present in the soil.
Make sure to discard the soil far away from your fiddle so the larvae don’t hatch and find their way back to your plants!
If your tree is otherwise healthy, you might be able to get rid of the issue by removing the soil containing fungus gnat eggs. This works best if your tree needs repotting anyway because of over-watering or being too root-wrapped.
Here’s how to repot a fiddle leaf fig.
Remember to repot your tree into a fresh pot or to clean the old pot if you’ll be reusing it.
Bacillus thuringiensis, or BTI, is a harmless bacteria that’s completely non-toxic for humans and animals, but is poisonous to insects and larvae. It’s also an approved insecticide in organic farming and is great for getting rid of pesky gnats!
Try sprinkling food grade BTI over the surface of the soil to kill off any larvae or eggs.
This is a powdered mineral with microscopic sharp edges. DE is harmless for your plant, but it kills insects when they eat it.
Make sure to wear a dust mask when working with DE to be extra safe, and it wouldn’t hurt to take your plant outside to do this if possible.
Flypaper and traps
Mature fungus gnats will die off on their own in a few weeks, especially if there are new no ones hatching, but you can move the process along with sticky traps or flypaper.
Simply hang a strip near your fiddle or put one right on the soil to attract pests.
Check out our other fiddle leaf fig insect guides!
Pests are a plant parent’s worst enemy, so be sure to read our other guides on ridding your fiddle leaf fig of pests!
- The Ultimate Guide to Fiddle Leaf Fig Insect Problems
- Surprisingly Invisible Places to Look for Mealybugs on a Fiddle Leaf Fig Tree
- How to Get Rid of Spider Mites on your Fiddle Leaf Fig
- How to Treat Scale on Fiddle Leaf Figs
Those pests won’t stand a chance!
Grab the Essentials for Your Fiddle Leaf Fig:
- Premium Fiddle Leaf Fig Potting Soil
- Fiddle Leaf Fig Plant Food
- Root Rot Treatment
- Houseplant Leaf Armor to protect against insects, bacteria, and fungus (As an added bonus, it also cleans and adds shine to your plant’s leaves!)
- Moisture meter to always know when your plant is thirsty.
To learn more:
- Sign up for our free Fiddle Leaf Fig Care 101 Webinar or enroll in our free Fiddle Leaf Fig Course for advanced fiddle leaf fig care.
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- Read The Fiddle Leaf Fig Expert, your complete guide to growing healthy fiddle leaf fig plants. The book is available in full-color paperback or Kindle edition on Amazon now!
- Click to join our community on Facebook: Fiddle Leaf Fig Plant Resource Group.