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Mosquito Dunks for fungus gnats--how much?

Posted by momma_s 9b, SZ14 (My Page) on
Wed, Feb 3, 10 at 15:21

I have 4 5 gallon buckets that are infested with fungus gnats from all the rain we've had. I've added more drainage holes on the bottom portion of all sides, and I've read other posts about using mosquito dunks soaked in water.

I've soaked 1 dunk in a gallon of water, but I haven't seen any specifics about application. Anyone know how much I should pour into each 5 gal. bucket? Thanks!

Follow-Up Postings:

RE: Mosquito Dunks for fungus gnats--how much?

About the only direction I have found for using the Mosquito Dunks for Fungus Gnat control is to scrape about a teaspoon off a dunk and mix that in 1 gallon of water. One source stated to crumble a dunk and sprinkle the resulting "dust" on your potting soil and then stop watering for a couple of weeks, which tells me that just drying out the soil is a more effective means of control.

RE: Mosquito Dunks for fungus gnats--how much?

  • Posted by morz8 Z8 Wa coast (My Page) on
    Thu, Feb 4, 10 at 10:55

momma, float the dunk in a container of water overnight, then use that water to water your container plants as you normally would. At least three consecutive times on your usual watering schedule, expect it to take three or four weeks to kill any hatching larvae and stop the breeding cycle.

I brought the gnats home in a new indoor plant once (I saw them around the plant in the store and didn't realize their significance) - ended up with them in every container plant, some that were decades old. I don't over water. My feeling is that keeping soil on the dry side might prevent them from establishing, it wasn't helpful in eliminating an infestation.

Years later, as I'm growing more from seed and need uniform moisture, I prefer the liquid form of BTi for convenience, but the dunks method does work.

RE: Mosquito Dunks for fungus gnats--how much?

Dunks are more concentrated than Gnatrol(about double), which is reccomended to be used at 1-3 teaspoons/gal. However the dunk does not release all of its active ingredient immediately.
Crush the dunk with a hammer BEFORE opening the blister pack
Use about 1/4-1/2 dunk soaked overnight per gallon of water and you can resoak the remaining solids again, or just water them on thus allowing a constant release over time.
Thorough soaking of the media is essential, as well as controlling all nearby breeding areas such as under benches and other places organic matter accumulates.
Cleanliness and 3 weeks of follow up are very important as only the larvae, not adults, are controlled.

RE: Mosquito Dunks for fungus gnats--how much?

I agree that overly moist potting medium is not always the problem. It CAN be, but not always. Fungus gnats seem to be pretty tough, once they become established.

I still say that if you amend your potting soil so that it is not so 'peaty', fungus gnats will pack their bags and say "adios".

RE: Mosquito Dunks for fungus gnats-- do they really work?

I have a problem with fungus gnats& larve I want to get rid of them I am a novice a growing can you help please they are all over my lava rocks in my hydroponic system

RE: Mosquito Dunks for fungus gnats--how much?

A new post, rather then using someone elses would have been better. However, one method to control Fungus Gnats in hydroponics is about the same as in potted plants add Gnattrol to your solution.

Here is a link that might be useful: Fungus Gnat control in Hydroponics

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