# Neoseiulus californicus

> A generalist-leaning predatory mite that eats spider mites and broad mites, survives on low prey or pollen, and tolerates warmer, drier rooms than Phytoseiulus.

- Canonical: https://genetixbay.com/knowledge/glossary/neoseiulus-californicus.html
- Also written: californicus, N. californicus, Amblyseius californicus
- Glossary category: Pests and diseases · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

*Neoseiulus californicus*, formerly *Amblyseius californicus*, is a phytoseiid [predatory mite](https://genetixbay.com/knowledge/glossary/predatory-mite.md) that prefers [spider mites](https://genetixbay.com/knowledge/glossary/two-spotted-spider-mite.md) but will also feed on [broad mites](https://genetixbay.com/knowledge/glossary/broad-mite.md), other small mites and pollen. It is pale and translucent, about 0.3-0.5 mm, and slower than *[Phytoseiulus persimilis](https://genetixbay.com/knowledge/glossary/phytoseiulus-persimilis.md)*. Its broader diet lets it survive when prey is scarce.

## In practice

Growers use *californicus* as a preventive, standing army: released across the canopy in veg, often in sachets, before spider mites are seen. It copes with warmer temperatures and lower humidity better than *persimilis*, which suits many indoor rooms. It eats fewer mites per day, so on a heavy outbreak it is paired with *persimilis* on hot spots. It is also one of the predators used against broad mites. Releasing it well before flower gives populations time to establish. Keep incompatible sprays out of the release window.

## Don't confuse with

- **Phytoseiulus persimilis**: a fast specialist that crashes without spider mites.
- **Amblyseius swirskii**: better on [thrips](https://genetixbay.com/knowledge/glossary/thrips.md) and [whitefly](https://genetixbay.com/knowledge/glossary/whitefly.md); needs warmth.
- **Neoseiulus fallacis**: a related species used mainly outdoors and in cooler climates.

## Related terms

[Phytoseiulus persimilis](https://genetixbay.com/knowledge/glossary/phytoseiulus-persimilis.md), [Two-spotted spider mite](https://genetixbay.com/knowledge/glossary/two-spotted-spider-mite.md), [Broad mite](https://genetixbay.com/knowledge/glossary/broad-mite.md), [Preventive release](https://genetixbay.com/knowledge/glossary/preventive-release.md), [Predatory mite](https://genetixbay.com/knowledge/glossary/predatory-mite.md)

## Read more

- [Spider mites on cannabis: life tables, ID and IPM](https://genetixbay.com/knowledge/pests/spider-mites.md)

## Sources

1. UConn IPM. Biological control of spider mites (2019 fact sheet). https://ipm.cahnr.uconn.edu/wp-content/uploads/sites/3216/2022/12/2019biologicalcontrolofspidermitesfinal2-1.pdf
2. UC IPM. Pest Notes: Spider Mites (Publication 7405). University of California ANR. https://ipm.ucanr.edu/PMG/PESTNOTES/pn7405.html