Fighting hair gnats | Neem oil, repellent spray & SF nematodes

1. General information about hair flies

Hair midges ( Bibionidae ) are small, dark-colored flies that visually resemble fungus gnats. They appear in large numbers, especially in spring, and are often seen around pots, beds, and lawns. While the adult midges themselves are harmless, the larvae in the soil can nibble on tender roots, weakening young plants and seedlings.

Hair flies multiply particularly rapidly in moist soils and nutrient-rich substrates. They can quickly become a nuisance, especially in greenhouses, pots, and plant containers .

2. Detect hair fly infestation – typical signs

You can recognize an infestation with hair flies by the following symptoms:

Small black flies (3–6 mm) buzz around plants or windows
Larvae in the soil – whitish, thin and up to 1 cm long
Weakened young plants that grow poorly or wilt
Moist soil as a breeding ground – especially in plant pots and beds

Hair fly larvae can cause considerable damage, especially to sensitive young plants.

With neem oil, you can support your plants naturally and boost their resilience – ideal for weakened roots caused by fungus gnat infestation.

Easy to use: Mix with water and spray onto the plants – uncomplicated and quick to use.
Plant-based care: Based on natural ingredients, free from synthetic additives and without unpleasant odor.
Long-lasting support: Strengthens the plants sustainably and supports them over several weeks.

Power Neem oil against fungus gnats

€19,90

€19,90 /item

3. Preventing hair gnats – Tips for home & garden

To prevent hair flies from becoming a nuisance in the first place, these measures will help:

Avoid waterlogging : Do not keep the substrate permanently moist, ensure drainage
Allow the upper layer of soil to dry out : Larvae prefer to develop in wet soil
Use clean planting substrate : Check soil before use and sterilize if necessary
Use yellow boards : They catch the flying adult hair midges and reduce egg laying
Check regularly : Especially in damp corners, in the greenhouse and in potted plants

With the SF nematodes, you can help your plants naturally control fungus gnats in the root area, thus ensuring strong, healthy growth.

Easy to use: Mix with water and add directly to the irrigation water – this allows the nematodes to easily reach the roots of the plants.
Natural & gentle: Beneficial organisms from nature, free from chemical additives and harmless to plants, humans and pets.
Long-lasting support: Works in the root area over several weeks and promotes healthy plant growth.

SF nematodes against fungus gnats, codling moths & ants

From €9,90

€2,48 /m2

4. GREEN GUARDIA products against hair gnats

GREEN GUARDIA Neem Oil Plant Care

Neem oil is a herbal remedy that is effective both as a preventative measure and in acute cases against hair fly larvae. Applied as a spray or water solution, it coats the plant and the soil, disrupting the larval development and sustainably reducing the population.

GREEN GUARDIA pest repellent spray

Our ready-to-use repellent spray reliably combats midges around plants. It can be sprayed directly onto soil, leaves, and infested areas, providing rapid protection against severe infestations.

GREEN GUARDIA SF nematodes against hair flies

SF nematodes are natural enemies of midge larvae. They actively penetrate the larvae in the soil and terminate their development. They are easily applied via irrigation water—ideal for pots, beds, and greenhouses.

👉 The combination of neem oil (preventive & growth-inhibiting) , repellent spray (immediate effect) and SF nematodes (permanent biological solution in the soil) is the most effective strategy to permanently get rid of hair gnats and keep plants healthy.

✅ Conclusion: Hair gnats are especially dangerous for young plants because their larvae feed on the roots. With the right preventative measures and GREEN GUARDIA products – neem oil, repellent spray, and SF nematodes – you can combat hair gnats quickly, effectively, and sustainably .