flying pests in greenhouse

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OK, I am relatively new to this greenhouse growing and last night when I was in there working I noticed little tiny fly's around one of my flats. The swarm took off while I was watering, I am trying to keep as organic as possible and hate the thought of using pesitcides. Anyone have any suggestions? Thanks, Mary

-- Mary (mlogan298@yahoo.com), May 23, 2000

Answers

Hello,

If they are tiny blackish things they are fungus Nats. They love greenhouses and moist soil. Try to let the soil dry out between waterings. The only way I have been able to get rid of them without pesitcides, is let the soil dry out,, then pour almost boiling water on the soil. So far it does not seem to bother the plants. If they are white or a very pale green, they are white flys. Lacewings will eat the white flys,, you can usually order them through gardening stores.

Hope this helps a little. :O)

-- Bergere (autumnhaus@aol.com), May 23, 2000.


You could try using fly tape/ribbon to trap them.

-- Jean (schiszik@tbcnet.com), May 23, 2000.

BTW, I just learned from working in a professional green house this spring that if they are fungus knats, the larvae will eat your roots in the pot, so they are more than just an annoyance.

-- Novina West (lamb@stellarnet.com), May 24, 2000.

Mary, some things you can try are fruit-fly trap like things and sticky yellow traps. You can make a simple fruit-fly trap by mixing a bit of yeast and some sugar in water and leave a jar or two near the flys. You can buy yellow traps or make them yourself. Look for cheap bright yellow kids's toys and cover them with something like Tanglefoot from a greenhouse. Regular house fly tapes aren't usually yellow enough to work as well, but hang them so they are down low in the plants and you'll get some. These aren't the best solutions but they might help. Drying out the greenhouse and cleaning it well are the best help, but that can be hard to do.

Don't forget to watch any trap you use to make sure it isn't catching good insects. Take the traps out if they are. Gerbil

-- Gerbil (ima_gerbil@hotmail.com), May 27, 2000.


Fungus nats can be killed by applying a drench to the soil. Three teaspoons of white ammonia to a gallon of water. This gets the larvae even in the root. Of course you still have to let the plant dry out between waterings. Two applications usually gets the pests.

-- Tom Hopkins (sycamore@bigfoot.com), April 16, 2001.


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