The simplest way to break that cycle and get rid of them is to water all your plants from the bottom only and not let the top of the soil get moist. To be doubly certain of results I always keep closer to 1 inch totally dry and extend this routine for closer to 3 weeks, just to make sure.
Also before bringing plants home look around if you see any fungus gnats flying around the plant display area. You can also check the top of the soil for them by gently disturbing the soil with your fingertip. If you see any you will be better off to find another place to buy your plants. I hope this helps.
By Sylvia from Cobalt, Ontario
I have been having a problem with fungus gnats in and around my potted plants. I was told that if I diluted regular Listerine, 1 to 1 with water and spayed the organic soil mixture, the solution, would kill fungus gnats and their eggs that live in the manure.
If anyone knows this to be true please give feed back. Have tried other solutions, but to no avail.
Hardiness Zone: 6a
By Lady Belle 13 from Philadelphia, PA
These things suck - become an unfortunate 'field of study' for me, haven't found one particular thing that works perfectly for me - but I thought I'd pass on a few things to consider, just in case anyone else missed them!
1. They seem especially drawn to two things first plants in pots that are too big for them (thus they are surrounded by damp soil that the root system isn't using). And fertilizer.
To remedy these things:
1. Stay away from miracle-gro potting soil (the cheaper potting mix seems to have a lot less problems.
2. Bake all potting soil - new or used - for an hour on 250-300 degrees F before using it. also when transplanting rinse the roots outside well and either dispose of the old soil or bake it.
3. Skip gravel/rocks in the bottom of the pot, and only water from the bottom using a saucer, after a few minutes toss any water left that the plant hasn't absorbed. Sometimes it takes a few waterings for the root system to figure out where the water is coming from but they will adjust, and skipping the gravel in the bottom of a pot speeds this up.
Note - Certain plants like philodendrons get them repeatedly, and I have had better luck putting them in a tall narrow vase of water instead permanently. Sometimes I just move outside.
4. Very important (as I too have a 'Charlie Brown Christmas tree' sort of tendency to feel sorry for sickly plants and try to nurse them back to health)
If you discover a plant that has these gross gnats (usu. in a bath or bedroom that you don't pay much attention to - you will recognize them by the fact that they 'run around' the edges of the pot more so than they "fly" and on the surface around it) bag the whole thing and throw it away, or like I do - toss it off of the balcony onto the lawn then later go with a garbage bag, wrap it up and throw it away! You will save yourself many headaches.
Then go around and check all of the plants inside and out, and even if you don't immediately notice any gnats, take the first couple of inches of soil off of the top of all of them and throw it away! : ) Replace it with new baked soil. Don't fertilize so often, and let the plants dry out between watering.
P.S. to the person who wrote about the 'decline' of plants after; this seems to be a direct result of these gnats. Either that the gnat larvae eating the roots of the plants, or because as a result of the infestation, predator nematodes (which feed on the larvae) themselves become a parasite to the plant. In my experience the plants almost never recover after this, even after changing the soil etc. Save the grief and toss the plant in the first place. They're not that expensive, and you probably have too many anyway.
Oh also - open up your windows more often more sunlight and fresh air is their enemy and you'll feel better (and your house will be a healthier environment). Do it now! Good luck!
Does anyone have a solution for getting these pests out of your house plants? I've used every solution posted for eliminating potential breeding grounds (and the flies themselves), but no one has touched on how to do this short of throwing away my plants.
By Allie A.
I have had success with a mix of water, liquid dish soap and vinegar, red wine vinegar seeming the best. In a small jar, such a a spice jar, put a little water and vinegar and just a drop or so of the soap, about an inch or so in the bottom of the jar. Mix well. You should be able to smell the vinegar. Into the mouth of a jar put a funnel of rolled paper, not touching the water mix, but projecting below the mouth of the jar. Set near the infested sight. Depending of the number of fruit flies, you may have to empty it every day or so and start with a fresh mix. I think it is the scent of the vinegar that attracts them.
Is there any way to get rid of gnats and larva in my new terrarium or do I have to dump all of the soil, rinse the plant roots and start over?
By Patsy A
I have a fungus on my grass. I had a commercial service which I gave up on it and after that is when I got this fungus. It seems the grass is very weak do to all the chemicals this company laid on it and the fungus just took over. Any suggestion on a natural product, I'm afraid to use any more chemicals. Thank you.
Hardiness Zone: 10b
Carlos from Florida
How do I get rid of fungus gnats?
Angelina from Raceland, KY
Control Measures
Prevention
Inspect plants carefully before purchase for signs of insect infestation. Always use sterile potting soil to prevent introduction of fungus gnats. Overwatering, water leaks and poor drainage may result in buildup of fungus gnats. Allowing the soil to dry as much as possible, without injury to the plants, is effective in killing many maggots. Houseplants taken outside during warm weather may become infested with insects before being brought back indoors. Inspect plants carefully and discard if heavily infested and unable to save. Remove all old plant material and debris in and around the home. Practice good sanitation. Electrocutor-light fly traps will attract and kill many adults at night.
Monitoring
Use yellow sticky cards (traps) for adult fungus gnat detection. Place traps just above the plants at a frequency of one per 500 to 1,000 square feet. Replace when covered with insects. Check traps 2 to 3 times each week.
Insecticides
Adult fungus gnats are killed easily with Pyrethrin spray or aerosols labeled for "gnats" or "flying insects". Repeat applications several times if necessary. Commercial mushroom growers may get control with Diazinon, Methoxychlor or Naled (Dibrom), whereas commercial greenhouse growers can use Bacillus Thuringiensis Berliner var. israelensis (Gnatrol, Vectobac). Licensed pesticide applicators can apply a restricted use pesticide, namely Oxamyl (Vydate). Always read the label and follow directions and safety precautions. Read More: http://ohioline.osu.edu/hyg-fact/2000/2114.html (12/18/2007)
By lewis_admin
I have to do my herbal garden in my apartment. I have fungus gnats, ugh. I got the little yellow flags that are sticky traps. However, it only catches them after they hatch, not while they are in the soil.
Because these are my herbs, I do not want to put chemicals on them. Can someone help me? I do not want to throw them out. I have a nice little garden, and I don't want to buy new plants and pots. Thanks.
By adriarobi from Oshkosh, WI
By frausnow
By ShelliM
Get a bag of sandbox sand from your home improvement center. If you can, cover the top of the soil of each plant pot with at least a 1/2 inch thick layer of sand. If your pot does not allow that minimum depth of a layer, you may have to re-pot and then top with sand.
If you feel that there are "critters" in the bag of sand, use a large disposable aluminum baking pan (you can re-use it for this process) and heat the sand in you oven for about 30 minutes at 350 F. Cool completely. Place this flexible pan on an old cookie sheet or pizza pan for stability before you put the sand in the pan and then into the oven.
I sure do hope these hints from the folks who responded help you with this frustrating and annoying problem. (06/14/2009)
By jeg51
By Dutch 1962
How do I get rid of gnats in house plants?
By Voncile from Montgomery, AL
By WildIrish
How do I get rid of gnats living in the soil of my houseplant?
By Rachael
By larflu
By GUAPO
I have gnats in my home, I think they are coming from my plants in the house. How can I get rid of them?
Hardiness Zone: 10a
By Delores65 from Corona, CA
By Laniegirl
I put a layer of sand on top of my potted plants to get rid of gnats, but have been seeing a decline in the health of my plants. Could it be from the sand?