First Grow

BlueRidgeGrower

Well-Known Member
Noticed small gnats in grow tent and had a friend who told me to get some diatomaceous earth so I sprinkled some over the soil. Hopefully he's correct and I did the right thing. Also OldMedUser I don't know how to put your name in this or whatever but I got a bluelab PH pen. Gotta go get some more solutions for it though because I immediantly spilled the hydration one and then bunked the calibration steps. Apparently I'm a little slow when it comes to these things. Having the lady at the store show me how it works tomorrow
 

furious248

Well-Known Member
You need to get your gnat problem under control before flowering or that is when the shit hits the fan, if nothing else you could use azamax, although it is safe for humans i wouldnt use it on a flowering plant just incase, and you dont want to ruin the taste of your buds... i find if there are gnats at flowering then i messed up and need to start again because they are almost impossible to get rid of without affecting the buds
 

BlueRidgeGrower

Well-Known Member
There's a noticeable slack in gnats so far. If it continues they should go bye bye fairly quickly. Can anyone educate me on the cause of said gnats?
 

Lachrymology

Well-Known Member
Fungus gnat larvae eat fungus or decaying matter, and need wet conditions to thrive. It is common for soil growers to overwater their cannabis plants, and wet soil is the perfect home for fungus and decaying organic matter. After fungus has grown (often invisible to the naked eye) or overwatered matter has begun to decay in the topsoil, fungus gnat lays their eggs in in the top layer of wet soil.

Warm + wet topsoil = fungus gnats
 

BlueRidgeGrower

Well-Known Member
Fungus gnat larvae eat fungus or decaying matter, and need wet conditions to thrive. It is common for soil growers to overwater their cannabis plants, and wet soil is the perfect home for fungus and decaying organic matter. After fungus has grown (often invisible to the naked eye) or overwatered matter has begun to decay in the topsoil, fungus gnat lays their eggs in in the top layer of wet soil.

Warm + wet topsoil = fungus gnats
So keep soil as dry as possible
 

Lachrymology

Well-Known Member
diatomaceous should cut em up good, combine that with good watering practices and you should keep them away for good. The adult gnats themselves aren't very dangerous (besides disease they CAN spread to the plants) its the larvae in the soil who can nibble up on your roots that the most immediate danger. You should be good just keep an eye out and let that first inch of soil get nice and dry before watering. First thing I learned, as a new grower, we have a tendency to give them a bit too much love. Looking good so far tho.
 

BlueRidgeGrower

Well-Known Member
I'm sure there's more in there but at least temporarily they've left. Plant looks happy. Your can't tell in these pics but the top of the stem to the leafs are kinda purple pinkish. Is that normal?20170523_230725.jpg 20170523_230750.jpg 20170523_230709.jpg
 

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Lachrymology

Well-Known Member
General stress, too high or low temp/RH, pH too high or low or a magnesium deficiency. Generally speaking if the plant is growing fine and they're slightly purple/red it's probably just genetic or they'll grow out of it.
 

Lachrymology

Well-Known Member
What are your temperatures at since adding your exhaust? Also make sure you have a passive intake for fresh air to come in.
 

BlueRidgeGrower

Well-Known Member
@BlueRidgeGrower
I have a similar setup to you. NL from Nirvana and learning as I go. So I'll be watching your thread. This is my journal:
https://www.rollitup.org/Journal/jmy137900.922645/
I'll be watching you as well friend!
What are your temperatures at since adding your exhaust? Also make sure you have a passive intake for fresh air to come in.
My temperature stay between 79 and 82. My humidity stays between 60s at water and then a few hours after water it's back down to 50s. I normally stay between 45 and 36ish. I have my exhaust fan blowing out of my tent and the little hole for the intake I leave open for air to pull through. It works really well
 

Lachrymology

Well-Known Member
However big your fan is (4inch or 6inch) you want around 2-3x the passive intake. I have a 6inch 440 CFM and I use three of the intake/exhaust openings on my tent and still maintain negative pressure. Also where are you exhausting the air to? If you're doing it into the same room as your tent it's going to keep those temps kind of high.
 

BlueRidgeGrower

Well-Known Member
I exhaust straight into same room. But it's summer and I run air conditioning pretty much all day. And I happen to have a Lil window unit for that room so it stays pretty cold if I want it too
 

Lachrymology

Well-Known Member
So you'd want 8-12 inches of intake. Usually those holes in the tent fit six inch ducting nicely. I'd get two of those going on the bottom of your tent and bend them to prevent light leaking out. Go for bottom since heat rises. You also really want to vent that exhaust air out the room so you're not recycling old/warmer air.
 
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