21 home remedies for fungus gnats: coffee grounds & co

Sciarid gnats (Sciaridae) can be extremely annoying, but they do not cause any harm themselves. The real pests of plants are their larvae. Home remedies should preferably be used to combat fungus gnats.

Recognize infestation

The fungus gnat invasion comes from the flower pot. If countless small flies appear there and float around the pot, the probability bordering on certainty is about fungus gnats. In their appearance they resemble the fruit or fruit flies. The mosquitoes love a humid environment. The moist soil in flower pots is just the thing. This is where the females lay their eggs. From these larvae and, last but not least, adult mosquitoes develop. These are:

• shimmering black
• 1 to 7 mm in size
• with long legs and antennae

The larvae generally stay in the wet soil or on the surface of the earth. When a plant suffers from a sciarid gnat infestation, the larvae are hard to miss:

• whitish to gray in color
• glassy appearance
• black head capsule
• Size up to 5 mm

Tip: Plants infected with fungus gnats must be quarantined immediately. Otherwise it can happen that other plants are also affected by the mosquito.

Harmful larvae

Adult fungus gnats are harmless to plants. The situation is different with the larvae. These feed mainly on organic material such as the roots. Infestation can have fatal consequences, especially for young plants, as they can inevitably die. By eating the roots, fungi can cause further damage to the plants. Typical characteristics for an infestation can be:

• Wilting phenomena
• hollow-eaten stems
• Stunted stature
• increased shrinkage of plants

As soon as fungus gnats are detected near flower pots, action must be taken as quickly as possible.

Home remedies to combat

Chemical agents can certainly be used to combat these animals. However, they can harm the environment, including humans and animals. Well-tried home remedies, on the other hand, are only dangerous for mosquitoes and larvae. Below is a small list of effective home remedies that can be used to fight sciarid gnats.
As soon as the first larvae are visible, quick action is required to avoid major damage to the plants. The following home remedies are quite effective.

Fight larvae

As soon as the first larvae are visible, quick action is required to avoid major damage to the plants. The following home remedies are quite effective.

Funds from the kitchen

Baking powder or baking soda

• Sprinkle a thin layer on the surface of the earth
• moisten slightly
• Larvae eat powder and die

Note: Baking soda works reliably in combating the larvae, but it should be borne in mind that the earth can become moldy.

Coffee grounds

• Dry the coffee grounds
• must not be moldy
• distribute on the surface of the earth
• Layer about 2 to 3 mm high

Note: Coffee grounds are not only a tried and tested home remedy for controlling the larvae, but are also an excellent fertilizer for the plant.

Cold coffee

• Let the coffee residues cool down
• Use half a cup of coffee
• Dilution in a ratio of 1: 1 with water
• Distribute liquid over the surface of the earth
• Caffeine kills larvae

Garlic (Allium sativum)

• either stick the whole tuber in the ground
• to do this, peel them and cut off the tip
• alternatively, chop individual toes into small pieces
• then distribute it on the surface of the earth
• in the case of severe infestation, a combination of both options
• sulphurous substance allicin kills larvae

nutmeg

• the myristic acid it contains damages larvae
• Sprinkle grated nutmeg on the surface of the earth
• with irrigation water powder gets deep into the earth

Parsley (Petroselinum crispum)

• Larvae cannot tolerate smell
• Chop a bunch of parsley
• distribute everything evenly on the surface of the earth

cinammon

• Cinnamon is also a tried and tested home remedy
• Sprinkle a thin layer on the surface of the earth

Animal control

bacteria

• the use of special bacteria such as Bacillus thuringiensis israelensis is also helpful
• secrete poison
• is not tolerated by larvae
• Administration with irrigation water
• recommended "Neudomück" and "Neudomück Pro"

Nematodes

• very effective in controlling larvae
• Use of nematodes of the species Steinernema feltiae (SF nematodes)
• microscopic nematodes
• Dissolve in lukewarm water
• mix well
• Administer with irrigation water
• Store opened packages of nematodes in the refrigerator
• Infestation done after one to two weeks
• Do not fertilize for three to four weeks after use
• Keep the soil evenly moist
• Use of tempered water

Note: As a rule, nematodes form stable stems in the soil. In this way, the plants remain sustainably protected against the larvae of the sciarid gnats.

Predatory mites

• are tiny
• mostly animals of the species Hypoaspis miles, H. aculeifer and Macrocheles robustulus
• commercially available in granular form
• simply sprinkle over potting soil

Mechanical methods

Replace the earth completely

• Thoroughly remove soil
• also remove soil from the root ball
• rinse with water
• Thoroughly clean pots
• Plant the plant in new, fresh soil
• alternatively use of used soil
• to do this, heat them in the microwave for at least 10 minutes

Quartz sand

• alternatively, use of bird sand, gravel or lime
• Application of a 2 to 3 mm thin layer on the surface of the earth
• gravel is advantageous
• here no mixing with soil when pouring
• When using sand, water the plant over a saucer
• Discard excess water after 20 minutes

matches

• Larvae cannot tolerate sulfur components on the ignition head
• 3 to 4 matches depending on the size of the pot
• Put it upside down in the ground
• Replace at least every two weeks

Tip: For a flower pot with a diameter of 10 to 12 cm, 1 to 2 matches are sufficient.

Oils

Lavender oil

• Add 20 drops to 1 liter of water
• Oil doesn't mix well with water
• therefore also add 1 tablespoon of soap nut powder
• acts like an emulsifier
• then mix everything well
• Use mixture for pouring

Tip: As an alternative or as a supportive measure, the oil can be poured into an aroma lamp and placed next to the affected plant.

Neem tree oil

• contains active ingredient azadirachtin
• harms larvae
• Mix 1 liter of water with 10 ml of oil
• Water the plant

Tea tree oil

• Add 20 drops to 1 liter of water
• mix well
• watering plants
• only killing larvae
• also use yellow boards

All home remedies are effective, but should be used several times depending on the infestation.

Fighting adult fungus gnats

Even if adult sciarid gnats do not cause direct damage, they are a nuisance and the females must be prevented from laying eggs.

vinegar

• Fill a large glass half full with water
• Add 50% vinegar and washing-up liquid
• mix well
• Detergent breaks surface tension
• place next to the affected plant
• Acetic acid attracts mosquitoes
• these drown

Fine stocking

• Pull fine stocking over the infected flower pot
• knot tightly
• Females are prevented from laying eggs
• Leave the stocking on the plant for at least 5 to 6 weeks

Fat plant (Pinguicula vulgaris)

• carnivorous plant
• catches insects with sticky leaves
• works in a similar way to yellow boards
• one plant per window sill is sufficient

Yellow panels or yellow plug

• yellow sticky cardboard strips
• simply put in soil next to the plant
• done after two to three months of infestation

dryness

• moist potting soil is an ideal breeding paradise
• Females lay eggs there
• Water plants only moderately
• Avoid waterlogging
• no harm to the plant for up to two weeks without watering
• Let the surface of the earth dry before watering again
• ideal watering over coasters
• remove excess water after 20 minutes
• In addition, remove and renew the top moist soil layer
• alternatively repotting in hydroponics or seramis

Note: Some swear by the Fighting fungus gnats also on the use of cigarette ash and disinfectants. Caution is advised here, these agents reach the roots with the irrigation water and poison the plants.

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