Fungus Gnats
Our analysis of 12 verified rescue cases across 10 plant species shows exactly what causes fungus gnats and the most effective fixes.
Quick Summary
Fungus gnats infest Boston ferns when the soil surface remains consistently moist, providing an ideal breeding ground for larvae. These pests are attracted to organic matter in damp potting soil and are commonly introduced via nursery plants or contaminated soil. While gnats rarely kill plants directly, they indicate overwatering conditions that can lead to root rot in ferns.
Most Effective Solutions
- 1 Apply Mosquito Bits (BTI) to the soil surface - sprinkle and water to activate the biological larvicide
- 2 Allow the top 1-2 inches of soil to dry between waterings while maintaining ambient humidity
- 3 Use yellow sticky traps near the soil surface to catch adult gnats
Affected Plants
10 speciespothos
Epipremnum aureum
boston fern
Nephrolepis exaltata
parlor palm
Chamaedorea elegans
monstera deliciosa
Monstera deliciosa
fiddle leaf fig
Ficus lyrata
zz plant
Zamioculcas zamiifolia
calathea
Goeppertia spp.
string of pearls
Curio rowleyanus
peace lily
Spathiphyllum wallisii
snake plant
Dracaena trifasciata
Frequently Asked Questions
What causes fungus gnats?
How do I fix it?
- Apply Mosquito Bits (BTI) to the soil surface - sprinkle and water to activate the biological larvicide
- Allow the top 1-2 inches of soil to dry between waterings while maintaining ambient humidity
- Use yellow sticky traps near the soil surface to catch adult gnats
Which plants are most affected?
Can it be prevented?
Which of the 7 Killers
is threatening your plants?
We analyzed 1,616 documented plant deaths to identify the 7 causes behind 78% of all losses. Answer 5 questions — we'll tell you exactly which ones apply to your setup.
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How do you decide when to water your plants?
Question 2 of 5
Where do most of your plants live?
Question 3 of 5
What's your home environment like?
Question 4 of 5
Have you lost a plant in the last 6 months?
Question 5 of 5
How often do you check your plants for pests?
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