top of page
  • Writer's pictureMitchell Stern

How to Get Rid of Spider Mites

Updated: May 23

Spider mites are tiny arachnids that wreak havoc on cannabis plants. They live outdoors and find their way into our homes and gardens during the warmer months. In terms of economic impact, spider mites are the most destructive pest associated with cannabis cultivation.

Spider mites are most commonly found outdoors and are more common in dryer regions with temperate climates and high levels of sunlight.

In this article we're going to discuss:

  • Signs & symptoms of spider mite infestations

  • How to get rid of spider mites

  • Garden cleanliness & pest prevention

Table of Contents

What Kills Spider Mites?

Spider Mite Taxonomy

Early Signs of Spider Mites

How to Get Rid of Spider Mites

Spider Mites on Plants


What Kills Spider Mites?

Neem oil will kill spider mites reasonably well; and is all-natural. However, the drawback to using neem oil alone is that it is only toxic to spider mites after they eat it. Neem oil has zero effect on spider mite eggs, which adult female spider mites lay in massive quantities.

Spider mite eggs take 5-7 days to hatch. Therefore, neem must be applied several times in seven-day intervals to successfully mitigate an infestation

Avid (Abamectin) used in conjunction with Floramite (Bifenazate) will kill spider mites in every stage of growth, including eggs.

These products are also systemic, which means that they stay in the plant for 8-10 weeks and should NOT be used on flowering plants.

We also recommend dipping new clones in an avid & floramite bath before introducing them into your garden.

Spider Mite Taxonomy

Spider mites may consist of one to two species that are collectively known by six different names and are separated by differences in morphology and ecology. Let's take a closer look at the two that pose the biggest threat to cannabis.

The two-spotted spider mite
The two-spotted spider mite

Two-Spotted Spider Mites - Tetranychus Urticae - (Koch 1886)

The two-spotted spider mite thrives in environments cooler than 86 degrees Fahrenheit (30 degrees Celsius) with low humidity

Eggs are spherical, approximately 0.14mm in diameter, translucent to white in color, and turn light yellow just before hatching. Larvae have six legs and two tiny red eyes.

Adults have eight legs and are yellowish-green; often with two large spots on their back. In late fall, the two-spotted spider mite turns bright orange-red.

Two-spotted spider mites generally emerge in spring and feed on plants that are particularly high in chlorophyll.

Females lay eggs on the undersides of plants, or in webs that they spin between the leaf blades. Each female lays approximately 200 eggs in her lifetime.

The carmine spider mite
The carmine spider mite

Carmine Spider Mite - Tetranychus cinnabarinus - (Boisdural 1867)

Eggs and larvae are similar to two-spotted spider mites, however carmine spider mite adults are plum red or brick red with dark markings. Adults have also been known to turn green in cooler climates, making them difficult to distinguish from two-spotted spider mites.

The primary difference between carmine spider mites and two-spotted spider mites is geography.

Carmine spider mites prefer warmer temperatures, typically 95 degrees Fahrenheit (35 degrees Celsius) or above.

For this reason, carmine spider mites are typically found in semi tropical regions.