Danny

It's most likely fungus gnats.

Make
sure there is no water sitting in any saucers, trays. Pick up all
debris (fallen leaves and so on). Roommate should do the same.

Get BTK - easiest way is to get mosquito dunks, they contain BTK, or see if you can find it in granular form. Sprinkle
over top of the soil, or dissolve piece of dunk in water you use to
water plants. You need to kill larvae, not the flies. There are few
'generations' of larvae since flies keep laying eggs. Repeat in about a
week or so. Once they are killed off, there should be no fungus gnats
(fruit flies).

-click to see mosquito dunks-

Hi Rina,

What does BTK stand for?

So i take one piece of dunk and dissolve on the water. Do I need to rinse my succulents after i water my succulent with dunk dissolved?

Can I use this also on my orchids? I just noticed my orchid has fruit flies as well? is it safe for orchid roots ?

Thank you so much

Danny

They aren't fruit flies, they are fungus gnats. Use some kind of bti treatment in the water (Mosquito Bits), and water sparingly for a few weeks if you can afford to do so (they thrive in a moist environment).

BTK is Bacillus thuringiensis var. kurstaki, which kills certain bugs without harming any other creatures or plants.

no need to rinse.

yes safe for orchids.

Wow - I've been in Florida for over 20 years. First time I have heard of mosquito dunks! Although not related to Danny's problem with fungus gnats, I really appreciate this information!

Thank you guys! :) I am going to kill all those nasty gnats! i though gnats does not fly! :)

Can i dissolve half of the mosquito dunks in 1 gallon of water? will it be effectively? or the half dunks is too much for 1 gallon of water?

thank you guys!

Danny

Danny

There are instruction about how much, I don't remember. No point of overdosing - the eggs hatch gradually, and repetition is needed. Adults are flyers, they are small flies, they don't live very long just enough to lay many eggs in succession. Larvae is what you need to get rid of.

In the long run, one should make sure that plants are not sitting in wet soil and the organic stuff (leaves, plant debris) is not left to rot - that's what they feed on.

I grind up only about a teaspoon's worth of a mosquito dunk for 5 gallons and it is plenty. A little goes a long way.

tj

Hmmmm - cleanliness in your growing area and no water standing around (as Rina mentioned) is important. I'm not saying it can't be, that you're using the gritty mix and have gnats, but I have well over a hundred plants that get watered very regularly and thoroughly and have seen maybe a dozen gnats in 20 years of using it. Do you have plants mixed in that AREN'T in the gritty mix? What went into your mix?

Al

Crenda, you definitely need some Bt in Fla. I just sprayed all my bromeliads to keep the tanks from getting skeeters.

Try raising your pots off solid surfaces - it will help water evaporate off and not give the gnats a hospitable home. Also try to kill any adult fliers.

I've had fungus gnats in gritty mix. If you water every week they can live in it. But it's a battle that is in your favor.

In combination with raising pots (great tip, and makes a noticeable difference in my experience) ensuring good air movement for indoor pots also helps, especially if you have groups of pots in close quarters. A small clip on fan can do wonders.

hi @tapla

I purchase my gritty mix for my succulents, bonsai and money tree from this website

http://www.bonsaijack.com/succulent_soil_111_gritty_mix.html

The only plants aren't in the gritty mix are my orchids. I have not watered them for two weeks and they are very dried inside right now.

I have all my plants more than 3- 4 months and i have never seen fruit flies until my roommate got his plant last week.

Now , those little monster are flying around my apartment and they are playing inside the gritty mix from my plants.

I have a trade with little water for my bonsai. I just threw out the water from my trade. The only plant that i water last week, it was my bonsai and money tree.

Al, should i get mosquito bits or mosquito dunks?

if i get mosquito bits, i just going to Sprinkle over the gritty mix and inside the moss of my orchids.

If i get mosquito dunks, i am going to make into small pieces of one dunk, and Sprinkle over the top of the gritty mix and my orchids. or just use a small piece of mosquito dunks and dissolved it into 1 gallon of water.

whats the best way to kill the eggs?

i am so sad right now :(

Dan - I don't think your succulents will be harmed, mostly fungus gnats are just annoying.

The pesticides kill the larvae, nothing really kills the eggs (without killing your plants).

Follow the package instructions is my suggestion. Personally, I used liquid BTk and just combined in my watering can at the recommended dose.

I'm guessing "Bonsai Jack" might not screen his mix, and much of what he says about how he mixes the soil doesn't make sense. For instance, he says that he replaces granite with calcined clay. Turface is calcined clay as well, and it does a job different than that of granite. No matter. I'm guessing your soil is probably much more water-retentive than

which is probably why the gnats find it hospitable.

I don't think it matters much what Bt v k you use - they all work. You might look to see if there are a lot of fines in the medium. It might help to screen it over a piece of aluminum insect screen; AND, it might be helpful to actually monitor how long the soil holds onto moisture. You might find that extending the in interval between waterings to also be helpful in keeping gnat population numbers within tolerable limits.

You can also lay potato slices on the surface of your soil. Larvae will migrate to the slices and you discard them when you change slices. That's also a useful way of gauging population #s.

Good luck

Al

B.t. kurstaki affects the larvae of butterflies and moths.....caterpillars, in other words. It will not work on the gnats.

The bacillus strain for members of the Diptera order is B.t. israelensis. It will help manage the larvae of FUNGUS GNATS, mosquitoes, and other relatives.

Rina was correct in her recommendation of mosquito dunks, except that the active ingredient is Bt-i, not Bt-k.

Rhizo - Good call, BTi is the correct one.

I checked my pesticide book - interesting to note that it lists BTk as phytotoxic to kalanchoe? BTi is not listed phytotoxic for anything (as expected).

Rhizo,

Thank you for catching it.

It looked foreign to me when I keyed it in - I knew better, too. Good catch. My bad.

Al

The important thing is to give Dan's roommate a reprieve, right? (Poor guy, lol)

Hi Rina,

I was upset of my roommate for couple days. He is buying the Mosquito dunks and mosquito bits, so I am happy with that now. I will update you guys next weekend if i see any mother tiny monster fruit flies around my plants.

crossing fingers! :/

Dan

Dan, good luck, it really should work. And sorry for getting 'carried' away without thinking by posting BTK instead of BTI - I also know better and didn't pay attention - at the same time I was typing, was thinking of btk killer...sheeesh. Am so glad Norma (rhizo) came along! But you have the right product.

In my first post, I said bti, and offered the commercial name mosquito bits. To repeat myself, I have only used the bits (occasionally sprinkling them in water as one would mosquito dunks). They have always completely eradicated the problem within 2-3 weeks, with a noticeable effect within days. I like the bits because they treat the soil every time you water, without you having to remember. They wash down into the orchid bark as well, and eventually break down and disappear.

I have heard that Bounce dryer sheets will get rid of fungus gnats. Not sure how or if other brands also work also. I think it may keep them from breeding in the pot but not kill them.