Fungus gnats are tiny black flies that hover near the planting medium. Their larvae feed on dead organic matter. They are vectors for plant diseases and should be eliminated from the indoor garden. There are several biological controls for this. Gnatrol (TM) is a strain of bacillus thuringiensis that attacks only fungus gnats. The bacteria are mixed in water and applied to the medium three times weekly. It kills the larvae, so the gnats are eliminated over several weeks, as the adult population dies off. $39 + shipping from 1PM Labs.
Nemasys (TM) is a strain of predatory nematodes, which attack gnat in the larval stage. One pack of 50 million nematodes covers an area of 3,600 sq. ft. The nematodes should be introduced weekly for three consecutive weeks to eliminate infections. Contact Bioscape, Inc., 4381 Bodega Ave. Petaluma, CA 94952. Phone: (707) 781-9233. Web site: www.bioscape.com. Scanmask (TM) is Steinernema feltros, a hybrid strain of nematodes, which uses chemical cues to find its prey. The nematodes enter the gnat and release bacteria that kill it.
The nematode feasts on the multiplying bacteria. It is available as a spray that can be watered into the medium or as a granular that can be mixed in medium. One application is all that is needed, as the nematodes are persistent. $29 + shipping from IPM Labs.
Spider Mites: To destroy spider mites, Stethorus punctillum is a type of tiny ladybug that eats both eggs and hatched spider mites. Each bug eats about 40 mites a day and many more eggs. About 100 bugs are needed to get a colony going. 100 bugs cost $67 from Nature's Control.
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