House Plants/insecticide


good morning will....I have a dracaena marginata plant...I had noticied small flying insects in my home,,,thought they were maybe a fruit fly...found that the home for them was the dracaena ,,,can you help with the ridding of these pests

Hi there,

The flying insects are called fungus gnats. The larvae (eggs) live in the soil of plants near the surface. As they mature, they develop wings and then fly about. The winged adults live for only about a week before dying. The key is to eradicate the larvae living in the soil.

The gnat larvae require constantly damp soil and rotting roots in order to thrive. The presence of fungus gnats are often an indication of over watering and root rot.

First, scrape off and discard any loose soil from the surface of the rootball. This loose soil serves no useful purpose but it is where many of the larvae are located. Next, allow the soil of your Marginata to dry at least an inch deep into the pot or until the leaves start to wilt just s bit. By allowing the soil to dry deeper into the pot, you will deprive the gnat larvae of the moisture they need to survive.

Some folks have success sprinkling a very thin layer of sharp builders sand over the surface of the rootball. The sharp edges of the sand carve up the larvae as they move about. If you use sand, make the layer very thin. Very few of the liquid pesticides on the market are effective and they tend to keep the soil too moist, so I don't recommend them or any other liquid home remedies.

I have written detailed articles on indoor plant pests and on Dracaena marginata care that I will email for free to you (or anyone else) who emails a request to me at I have also written an indoor plant care book in a PDF format that I can sell you if you contact me at my email address.

Please let me know if any of this is unclear or if you have any additional questions.

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It will take a couple of weeks, but you should see a gradualdecline in teh flying gnats once you remove teh excess soil and allow the remaing soil to dry out

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Will Creed


I am the only expert in this category with professional hands-on experience and knowledge of all indoor plants. I can answer questions regarding light, water, fertilizer, repotting, pruning and humidity and temperature requirements. I can identify plant pests and provide information on safe, effective treatments. My answers are based on 35 years of professional experience and scientific research and are clear and easy to understand. I do NOT use search engines to find answers to your questions. If you read my previous posts here, you will get a good idea as to how thorough and professional my answers are.


I have over 35 years of professional indoor landscaping experience caring for plants in homes, offices, building lobbies, stores, restaurants, and other adverse environments. I have written extensively on the care of indoor plants, including a 260 page book. My specialties include Ficus trees, low light plants, repotting, pest control, and re-blooming holiday plants. Be sure to check my ratings and nominations to learn why I am the top-rated indoor plant expert. I am the only House Plant expert consistently ranked in the AllExperts Top 20.

BA, Amherst College

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