Please confirm if these are fungus gnats.

Forsure

Well-Known Member
Added sand last night and today no signs of any flying fun guy gnats.
I’m happy about that.

If they are coming out the bottom of the pots drain holes, I’ll have to do something else.
Again was thinking h202 in my bottom watering.

will swap out my sticky traps and update in a few days.
Their natural response when the eggs hatch is to go to the surface so you should be ok they shouldn't head to the bottom, just keep an eye out for adults and if they are still around use a effective spray and break the cycle. Use sand in your future grows as a preventative measure against the little buggers.
 

MaybeOld

Well-Known Member
This is the best example I can find of what to look for.
Look at the thorax first, then wing size relative to body.
They can fly around for 10+ days, so plan on keep up on monitoring and treatment for a couple weeks

Thanks for this, was trying to explain the difference to a friend the other day
 

hotrodharley

Well-Known Member
Diatomaceous earth has an advantage over sand in that anything crawling to the plants get sliced up. Sand doesn't do that. Caterpillars are especially susceptible to DE.
 

Markshomegrown

Well-Known Member
There gnats in my veg and flower room, 1" of sharp sand helps and letting the soil dry out, keeps them at bay.
Don't think they do any damage to my plants

Existing fungus gnat larvae can be trapped using pieces of raw potato. Place the potato pieces flesh side down on the soil, and check under them every couple of days. Remove any feeding larvae, and replace the potato with fresh pieces. Do not let the potatoes dry out.
 
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Drop That Sound

Well-Known Member
They can still go through the drain holes too. Keep an eye out.

Wrapping a panty hose around the whole pot (while tying it off around the stalk) works best IMO. XXL size will fit around most smaller sized pots.

You can still water right through it, and get runoff.

They can't fly in or out of the fabric and will eventually die off.

No messy sand or DE to worry about.
 

Buddernugs

Well-Known Member
Iv done a 1% total strength h2o2 soak for 15 min then flush feed every day for 14 days in coco and wiped them out 100%
 

Severed Tongue

Well-Known Member
I originally tried what has been suggested by everyone, nothing worked.

What finally worked for me was using fabric pots and only bottom watering until no more presented on yellow sticky paper. Took about 3 weeks.

Then I resumed normal top water until runoff.

3 runs indoor in tents, has worked everytime.

Just wish it would work for aphids or thrips!
 

Horselover fat

Well-Known Member
Existing fungus gnat larvae can be trapped using pieces of raw potato. Place the potato pieces flesh side down on the soil, and check under them every couple of days. Remove any feeding larvae, and replace the potato with fresh pieces. Do not let the potatoes dry out.
Did this actually work for you? I tried it once and no larvae were interested in the potatoes.
 

Lockedin

Well-Known Member
Why do I feel like I need to go cut up a potato for the grow room? bongsmilie

I used 1/2" of DE successfully.
Watered to runoff - then top-dressed the DE.

I used scanmask nematodes on the next grow and never saw any pests at all.
 
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