Fungus gnats are impossible to ignore once you see them flying close to you or over your plants.
You’re determined to get rid of these silent, little flies once and for all since they somehow manage to annoy you just as much as obnoxious house flies.
What Are Fungus Gnats?
Known also as dark-winged fungus gnats, fungus gnats are tiny flies that belong to the Sciaridae family and the Bradysia and Orfelia genera.
These flies are primarily an annoyance pest, while they can be bothersome and appear filthy as they fly around your plants, your head, and light sources.
The adults are not dangerous. However, their soil-dwelling larvae, which resemble maggots, can harm plants, particularly young ones.
The larvae consume fungus, algae, and decomposing organic materials in the growth medium, but if populations are abundant, they may also nibble on root hairs and roots.
They can spread plant illnesses like black root rot, which is brought on by several species of Thielaviopsis, Pythium, Verticillium, Botrytis, and Fusarium fungi, through feeding.
Plants with severe damage may wilt. To give you time to deal with them, you will typically see the fungus gnats themselves resting on the growing media or flying around before this occurs.
Adults are eight-tenths-inch long, black-bodied flies with segmented antennae that are longer than their heads. When they are at repose, their wings, which are dark and translucent, fold over their backs.
Fungus gnats are small, black, and delicate insects that are frequently mistaken for fruit flies or shore flies. read more about how to distinguish between them
Biology and Life Cycle
A fungus gnat’s life cycle can be completed in as little as three to four weeks at a typical room temperature of 65 to 75°F. On indoor plants, reproduction happens all year round and generations mix.
Adults have an extremely brief lifespan and don’t eat. Females have a lifespan of seven to ten days, during which time they lay 200 eggs into moist growth media, preferring varieties with a lot of peat moss.
The eggs hatch into larvae in three to six days. The top two to three inches of the soil or soilless growing medium are where the maggots spend their entire lives feeding on fungi, algae, and decomposing organic matter.
When there are lots of them, they could start eating the root hairs of plants, which might harm the roots.
Before pupating close to the soil surface, the larvae go through four instars over a period of one to three weeks. The adults will appear in four to five days.
Sticky traps are another option for keeping an eye on these gnats within your house, but they aren’t the most attractive addition to your lovely houseplants.
You will be able to tell if your indoor plants have fungus gnats. Watch for them flying against your windows and other light sources, hovering about your plants, resting on the soil and foliage, or circling around your plants.
Organic Control Methods
When swarms of small flies are bothering you and your plants, it is tempting to resort to extreme measures, but keep in mind that you share the same environment as your plants.
Whatever you use to treat them ought to be safe to use around your family, including your kids and pets.
Fortunately, there are several risk-free, efficient strategies you may employ to eliminate fungus gnat infestations in your houseplants.
Cultural and Physical Control
Every reliable site you consult will recommend changing the surroundings if you’re looking for a quick and efficient technique to get rid of these little flies.
Overwatered houseplants are frequently linked to fungus gnat infestations. Sure, it’s often easier said than done to avoid overwatering your plants, but saturated potting soil is ideal for the development of wiggling baby fungus gnats and is particularly alluring to laying females.
As an alternative, you can bottom water your plants to prevent the soil surface from ever becoming wet, which is where eggs are laid and larvae tend to congregate.
When you see any decaying leaves or other plant parts, remove them immediately.
The females won’t lay their eggs on the surface if you cover it with half an inch of coarse sand or fine gravel.
You can try several biological control options in addition to – or instead of – the cultural controls mentioned above. Many of these concentrate on the soil-dwelling larvae or pupae.
Application of Steinonerma feltiae nematodes to the soil will aid in controlling the larvae.
Pesticides are not very efficient against this type of insect and need to be applied repeatedly to the soil surface in order to capture the adults as they emerge, especially contact pesticides like soaps and oils that do not stay for very long. Air mist shouldn’t be used where adults are flying.
Chemical Pesticide Control
When it comes to pesticides, persistent chemicals like neonicotinoids and pyrethroids are the best choices to employ against fungus gnats.
Chemical pesticides are not advised for use in residential settings, and the majority of chemical choices are only required in business settings when infestations are extremely bad.