Stratiolaelaps scimitus is a predatory mite of the family Laelapidae that lives in the top layer of soil and soilless media. It was long sold as Hypoaspis miles, and many growers still call it Hypoaspis. It is tan-brown, about 0.5-1 mm long, and eats fungus gnat larvae, thrips pupae, springtails and other small soil organisms.
In practice
Growers sprinkle it on the medium surface of mothers, clones and veg plants as a preventive layer against fungus gnats and soil-pupating thrips. It survives for weeks on organic matter and alternative prey, so one early release can persist through a run. It does best in moist but not waterlogged media and is less suited to bare rockwool or deep water culture, where it has nowhere to live. It pairs well with Steinernema feltiae nematodes and with foliar predators that cover the leaf stage of thrips. Some growers report it helps against root aphids, but evidence is thinbeing reviewed.
Don't confuse with
- Steinernema feltiae: a nematode that infects larvae rather than eating them.
- Dalotia coriaria: a rove beetle used for the same soil pests.
- Springtails: harmless soil insects often seen alongside.
Mites, mostly of the family Phytoseiidae, released as biological control to eat pest mites, thrips larvae, whitefly eggs or fungus gnat larvae.A soilless medium contains no mineral soil, such as peat, coco, rockwool or perlite blends, and relies mostly on the grower to supply nutrients.Small dark flies of the genus Bradysia (family Sciaridae) whose larvae live in wet growing media, feeding on fungi, organic matter and young roots.Slender insects about 1-2 mm long, chiefly western flower thrips (Frankliniella occidentalis), that rasp leaf surfaces, leaving silvery streaks dotted with black frass.Overwatering is watering so often that the medium stays saturated, starving roots of oxygen, which causes drooping, slow growth and root disease.DWC (deep water culture) suspends a plant's roots in an aerated nutrient solution, typically in a bucket with a net pot lid and an air stone.An entomopathogenic nematode applied as a soil drench whose infective juveniles enter fungus gnat larvae and thrips pupae and kill them with symbiotic bacteria.Aphids that colonise roots and the crown below the medium surface, on cannabis chiefly the rice root aphid (Rhopalosiphum rufiabdominale), causing slow, unexplained decline.
