spider mites and fungus gnats. - Ask Extension
I know in have fungus gnats, but still not 100% sure about the spider mites. I don't have permits in my soil so they stay longer than they should. App...
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spider mites and fungus gnats. #229984
Asked March 07, 2015, 11:29 PM EST
I know in have fungus gnats, but still not 100% sure about the spider mites. I don't have permits in my soil so they stay longer than they should. Apple cider vinegar isn't attracting them. I was thinking of using hydrogen peroxide but that''ll harm the healthy microbes in my soil. As for the spider mite I just found a little spider lookimg thing on a thin flimsy web between my soil and lower leaf. I killed itand checked the underside of my leaves for eggs but couldn't find anything. Temps are low 60's for about 8 hours and mid 60's for about 16hrs and temps outside are below freezing. What should I do
Windham County Connecticut
Expert Response
Dear Gardener,
Fungus gnats are fairly easy to control. Simply allow the top of the soil to dry slightly between waterings, and make sure there is adequate drainage below the pot. The pot should be raised above any water in the drainage dish. You can use small stones under the pot to raise it up.
To answer your question about spider mites, it would be helpful to know if these pests are in the house or a greenhouse, and what types of plants are affected. However, this article may help you determine whether they are in fact spider mites, and some possible controls:
http://extension.umass.edu/floriculture/fact-sheets/twospotted-spider-mites
The following also contains some good information, but note that it is written for California:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7405.html
Water can be both a prevention and a control for spider mites. They thrive in dry conditions, especially if the plants are stressed. A strong streamof water will usually dislodge them and reduce their numbers considerably.
Outdoors, many insecticides actually make spider mite problems worse by killing the natural predators. Spider mites often become resistant to the chemicals. We do not recommend use of vinegar for pest control. Vinegar can damage and even kill plants if applied to the foliage, and will also kill natural predators.
Fungus gnats are fairly easy to control. Simply allow the top of the soil to dry slightly between waterings, and make sure there is adequate drainage below the pot. The pot should be raised above any water in the drainage dish. You can use small stones under the pot to raise it up.
To answer your question about spider mites, it would be helpful to know if these pests are in the house or a greenhouse, and what types of plants are affected. However, this article may help you determine whether they are in fact spider mites, and some possible controls:
http://extension.umass.edu/floriculture/fact-sheets/twospotted-spider-mites
The following also contains some good information, but note that it is written for California:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7405.html
Water can be both a prevention and a control for spider mites. They thrive in dry conditions, especially if the plants are stressed. A strong streamof water will usually dislodge them and reduce their numbers considerably.
Outdoors, many insecticides actually make spider mite problems worse by killing the natural predators. Spider mites often become resistant to the chemicals. We do not recommend use of vinegar for pest control. Vinegar can damage and even kill plants if applied to the foliage, and will also kill natural predators.
