Fungal Gnats in My Tomato Box
I grow tomatoes in a 2' x 3' x 4' wood box in my basement under grow lights. I got gnats. Can these little critters mate in complete darkness? I've yanked the last tomato plant and I can now shut all lights off long enough to go through a life cycle. Also, do they mate down inside the dirt, or outside?
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rainbowgardener
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They like the dark. I believe the adult flies mate above ground, but lay their eggs into the potting soil and the larvae hatch out and live in the soil.
They require moisture in all phases of their life cycle and can generally be controlled just by making sure you let the top few inches of the soil dry out thoroughly between waterings. This can be difficult with earth box/ self watering containers and with moisture control types of potting soil. In this case it may help to spread a layer of sand on top of the soil, just to have a dry surface. Having good air circulation with a fan helps also.
Adding some cinnamon to the water you water with helps. It is a natural anti-fungal, which helps control the fungus that the larvae live on.
They require moisture in all phases of their life cycle and can generally be controlled just by making sure you let the top few inches of the soil dry out thoroughly between waterings. This can be difficult with earth box/ self watering containers and with moisture control types of potting soil. In this case it may help to spread a layer of sand on top of the soil, just to have a dry surface. Having good air circulation with a fan helps also.
Adding some cinnamon to the water you water with helps. It is a natural anti-fungal, which helps control the fungus that the larvae live on.
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gixxerific
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https://en.wikipedia.org/wiki/Fungus_gnat
Most likely fungus gnats, I have a true hatred for them. They are in my house 11 months out of the year it seems if not 12. There are a few methods I have seen to get rid of them. As Rainbowgardener said letting the top few inches at least dry out in between watering's is helpful since the larvae can not survive without moisture. A drench of BT, a bacteria, can help as well, also you can get nematodes that work on the larvae. the latter 2 I have not tried. Whatever method you use you must do it for several weeks to get the scattered birth cycle. Cinnamon (in light doses it can be a herbicide if too strong) and Chamomile tea can be added to the water to help.
I try my best to bottom water and that helps. I have a bunch of trays for my pots that were inexpensive. I bought them from Lowes. Not sure if you could build something underneath your system to bottom water or not but that is an idea.
Welcome to the boards I am just outside of St Louis.
Dono
Most likely fungus gnats, I have a true hatred for them. They are in my house 11 months out of the year it seems if not 12. There are a few methods I have seen to get rid of them. As Rainbowgardener said letting the top few inches at least dry out in between watering's is helpful since the larvae can not survive without moisture. A drench of BT, a bacteria, can help as well, also you can get nematodes that work on the larvae. the latter 2 I have not tried. Whatever method you use you must do it for several weeks to get the scattered birth cycle. Cinnamon (in light doses it can be a herbicide if too strong) and Chamomile tea can be added to the water to help.
I try my best to bottom water and that helps. I have a bunch of trays for my pots that were inexpensive. I bought them from Lowes. Not sure if you could build something underneath your system to bottom water or not but that is an idea.
Welcome to the boards I am just outside of St Louis.
Dono