Red Spider Mite

Tetranychus urticae

Glasshouse red spider mite, Red Spider Mite , Two spotted spider mite

profile iconTetranychus urticae (4884149094)
by Gilles San Martin (CC BY-SA 2.0)
1 of 8
profile iconTetranychus urticae (4884149094)
by Gilles San Martin (CC BY-SA 2.0)
1 of 8
Tetranychus urticae is a tiny red arachnid, belonging to the Acari (mite) family, known as Tetranychidae. It is barely visible to the naked eye and commonly known by the name Red Spider Mite. They are most commonly found in greenhouse or tropical houses, where temperatures are warmer and they measure approximately 0.4mm in length. They spin very fine webs on and under leaves which are a good sign of infection to watch out for.


Feeds off of the cells in leaves which in turn leaves pale spots on the plant.


Tetranychus urticae are extremely small mites that you can barely see with the naked eye, hence they are fairly tricky to diagnose. They are deep red in colour and when squished they leave behind red stains. They measure around 0.4mm in length.


Pale spots or scars can be seen in the leaves on damaged plants where the mites have been feeding off of the cells inside the leaves.











Worldwide, commonly found in glasshouses.

Biological treatment

Raise humidity and ventilate glasshouses to increase air movement as this pest thrives in low humidity and high temperatures with little air movement. Within a heated glasshouse, year-round the a predatory mite Phytoseiulus persimilis may be used as a form of biological control. It is very effective as it consumes spider mites at all stages of their life cycle.

Chemical treatment

Bioneem / Biocure soprays are effective. However, there are many alternative and less harmful methods of control. If a chemical option is sought, check with your local garden centre and please take care to follow the manufacturers' instructions. Check with your local regulating body for guidance on active ingredients and their authorisation for use.

Attracts this pest

Pears, tomatoes, ornamental cut flowers, cape gooseberries.

Be the first to hear what's coming next

Plants make people’s lives better so we’re building a place where community meets knowledge.