Amblyseius andersoni, also sold under the name Anso-Mite, is a predatory mite that excels at controlling a broad range of small pests—including young thrips larvae, non-webbing spider mites, rust mites, and even whiteflies. These mites are especially useful in cooler outdoor fruit crop conditions or cool greenhouse conditions. This environment is favorable for them to survive.

Here’s What They Look Like at Different Stages of Their Life

• Eggs: Oblong and transparent white, usually laid on the underside of leaves near veins.
• Larvae: Six-legged and only slightly larger than the eggs. These larvae are “facultative feeders”. They can eat, but they don’t have to to reach the next stage.
• Nymphs: Eight-legged protonymphs and deutonymphs. They are a pale whitish-yellow.
• Adults: About 0.4–0.5 mm long, droplet and elongated in shape, with a translucent white body. Males are smaller than females. Both male and female colors can shift slightly depending on what they’ve eaten.

Behavior: These mites are very mobile, travelling across leaves (especially undersides) in search of prey. They often rest in the axils of leaf veins.

Why growers love it:

• Very effective against a broad range of pests, including thrips larvae, spider mites, rust mites, and more.
• Remains active at lower temperatures, making it ideal for early-season applications or cooler greenhouses.
• Can survive on pollen, allowing it to establish sooner in flowering crops (before pests arrive).
• Integrated seamlessly into IPM programmes, especially when paired with other beneficials like Orius.
• A chemical-free solution that improves plant health and maintains ecological balance in your crop.

Timing is critical to achieving success with predatory mites. They perform best when introduced before pests reach outbreak levels.

Preventive Use:

• Introduce Anso-Mite early in the crop cycle, especially if thrips or non-webbing mites are expected.

Curative Use:

• Apply when you spot young thrips larvae, mite eggs, or early spider mite activity.

Environmental Conditions:

• Works well at temperatures above 14 °C (57 °F). Optimal activity is between 20–28 °C (68–82 °F).
• Less effective if relative humidity drops below ~65%.
• Not recommended for tomatoes. Its establishment is hindered by the glandular hairs on tomato leaves and stems.

Note: Monitoring is essential. Inspect leaves, flowers, and fruit clusters weekly to determine if additional releases are required.

1. Gently rotate the Anso-Mite bucket before opening to ensure the mites are evenly distributed. If using sachets, just hang them directly on the plants.
2. Sprinkle the mites lightly over leaf surfaces. Focus on lower leaves and areas where pests tend to congregate.
3. After release, avoid disturbing the crop for a few hours so mites can settle and begin exploring.
4. Use 50–250 mites per m² per release, adjusted based on climate, crop type, and pest pressure.
5. Perform at least 3 weekly releases, or until you achieve effective control. If using the sachets, apply them every 3-4 weeks to maintain control.
6. Bulk applications can also be applied using a Natutec Airobreez device to distribute mites more evenly in dense canopies.

Tips for each formulation:

• Bucket: Shake gently before distributing. Apply directly to leaves, flowers, and fruit clusters.
• Plus: Hang sachets throughout the canopy; no need for weekly intervention.
  

Selecting the right formulation depends on crop, growing space, pest pressure, and your IPM strategy. Preventive programs and low-humidity growing spaces often benefit from sachet formulations, while high-humidity greenhouses with high pest pressure will only require Bottle releases.

Tracking both predator and pest populations ensures Amblyseius andersoni delivers consistent results:

• Weekly inspections: Look for mites and prey on leaves, flowers, and fruit clusters.
• Sticky traps: Monitor thrips, mites, and whitefly activity to gauge control effectiveness.
• Supplemental releases: If pest populations are high or mites have not fully established, follow up with additional releases.

A well-maintained predator population can maintain pest control long-term, reducing the need for chemical interventions.

• Use as part of a preventive strategy to build a predator population before pests get out of control.
• Maintain relative humidity above 65% for best performance.
• Apply with care. Avoid disturbing leaves right after release.
• Track pest and predator populations weekly using sticky cards or leaf sampling.
• Consider combining with other beneficials like Orius, Chrysoperla, or nematodes in an IPM framework for broad pest coverage.