Predatory Soil Mite — Hypoaspis miles (Stratiolaelaps scimitus)
How to say it: hy-poh-AS-pis MY-leez / (stray-tee-oh-LEE-laps SIM-ih-tus)
A natural soil predatory mite for subsurface pests.
What Predatory Soil Mites Are
Hypoaspis miles—now classified as Stratiolaelaps scimitus—is a tiny, tan to light-brown predatory mite that lives in the upper layer of soil or growing medium where some pests live out their most vulnerable life stages. Like most soil-dwelling predatory mites, H. miles avoids light and stays buried rather than roaming across the surface in the open.
What Hypoaspis miles Eats
Primary target: Fungus gnat larvae. This is the pest H. miles predatory mites are best known for controlling, and the reason most growers add them to their setup in the first place.
Also targets:
- Root aphids — feeds on root aphids working the root zone, a pest that's easy to miss until damage is already visible above ground
- Thrips pupae — consumes thrips larvae that spend the pupal stage in the soil, making this a useful piece of a broader thrips IPM program
- Shorefly eggs and larvae — larvae can survive in very wet soil or standing water where H. miles is not as effective. Consider Dalotia coriaria (rove beetle) for overly wet conditions.
- Springtails — preys on all life stages of springtails in the growing medium
- Other soil-dwelling mites and small soil arthropods it encounters while foraging
- Falls back on algae and organic debris when prey is scarce.
How Hypoaspis miles Works
Sold as a mix of eggs, nymphs, and adults in a bran or vermiculite-based carrier for direct application to the soil surface. H. miles burrows down and lives and hunts in the topmost layer of soil, moving quickly across the surface in low light conditions, or just beneath it in search of prey.
Reproduction is steady rather than explosive. Females lay eggs directly in the soil, and the full egg-to-adult cycle typically takes about 13–18 days under warm, humid soil conditions — faster in warmer soil, slower as conditions cool. Adults can live over two months, which means an established population keeps working long after the initial release.
When to Apply Hypoaspis miles
H. miles has no diapause phase, so it stays active and useful year-round rather than going dormant when daylight hours decrease — a genuine advantage for indoor growers and year-round greenhouse operations. That said, timing still matters for results:
- Preventive — Apply at transplant or at the beginning of a growing cycle.
- Early infestation — Apply when fungus gnats or root aphids are first noticed.
- Heavy infestation — Use a heavier initial application and repeat as needed.
How to Apply Hypoaspis miles
- Check your growing medium. It should be moist but not waterlogged, with a loose, open structure.
- Gently roll the container to redistribute mites evenly through the carrier material.
- For dry soil, lightly water the area 10-15 minutes before application. It should be moist, not overly wet.
- Apply directly to the moist soil surface around plant bases and areas with pest activity. Do not apply to foliage.
- Avoid overhead watering or heavy irrigation for 2-3 hours after application.
- Avoid broad-spectrum pesticide applications immediately before or after release.
- Monitor and reapply as needed.
Application Rates for Hypoaspis miles
12,500 predatory mites covers up to 625 square feet
25,000 predatory mites covers up to 1,250 square feet
125,000 predatory mites covers up to 6,250 square feet
These are general starting points. Actual application should be adjusted based on pest pressure/species, plant type, and infestation severity.
Temperature
Soil temperature: Active above roughly 54–59°F
Best performance: 60–77°F
Moisture: Keep soil moist, but not waterlogged
Pairing & Compatibility
Compatible with beneficial nematodes as part of an integrated pest-management program.
Avoid co-application with Dalotia coriaria (rove beetle), an aggressive generalist predator that will eat many types of small, soft-bodied soil pests, including beneficial predatory mites.
Safe, Sustainable Pest Management
- 100% natural biological control agent
- Safe around people and pets. They don't bite, sting, or carry any risk to people or animals.
- IPM-compatible
- No PPE required
What to Expect on Arrival
Don't worry if you open the container and don't see much movement on top of the carrier material right away — H. miles is photophobic and burrows away from light almost as soon as it's exposed. This is normal and doesn't mean anything is wrong with your shipment.
Predatory soil mites can be sluggish in cool temperatures. Allow the container to rest at room temperature for about 30 minutes before checking for viability.
To Check Viability:
- Quick check: Open the lid under normal room light and look closely right away — you'll see tan, poppy-seed-sized mites scurrying and burrowing away from the light. That movement alone is a good sign of a healthy, active shipment.
- Soft light check: Turn off nearby lights or move to a dim room for a few minutes, then use a flashlight covered with a paper towel or a piece of thin cloth. The softer light lets the mites stay out in the open longer so you can watch them move rather than just catching a glimpse before they dive for cover.
- You can also scoop a small spoonful of carrier material onto a sheet of white paper. Shine a flashlight across the paper at a low angle — you should see tan, poppy-seed-sized mites moving briskly across the white background within a minute or two.
Storage
If you can't release right away, keep the container in the coolest spot in your home that's out of direct sunlight. Avoid the refrigerator, and anywhere warm like a sunny windowsill or near appliances. Plan to release within 24 hours for best results.
FAQs
What's the difference between Hypoaspis miles and Stratiolaelaps scimitus?
Nothing is different. Taxonomic research reclassified it from Hypoaspis miles to Stratiolaelaps scimitus. Only the scientific name changed, which is why you'll still see "Hypoaspis miles" on packaging and hear growers ask for it by that name.
Are Hypoaspis miles good or bad for my garden?
Good! They're a beneficial predator, not a pest. They don't feed on plants, roots, or foliage; they hunt other small soil-dwelling pests like fungus gnat larvae, root aphids, and springtails.
Can Hypoaspis miles become an infestation themselves?
Not likely. As prey populations decline, their numbers decline too. They can persist at low levels by feeding on algae and organic debris, but they don't multiply out of control the way a pest species would.
How do I apply Hypoaspis miles?
Distribute the carrier material directly onto the moist soil surface — never onto foliage — focusing on plant bases and any areas of known pest activity, then water lightly to help mites move into the soil.
Can I use Hypoaspis miles for snake, poultry, or varroa mites?
It works on the mites living and hiding in the substrate — not the mites attached and feeding on the snake, chicken, or bees. It's best understood as reducing the pests mite in the environment alongside whatever direct treatment the animal itself needs.
Are Hypoaspis miles safe in a worm bin or vermicomposting setup?
Yes. For established composting worms H. miles is commonly used to knock down nuisance mites, gnats, and other small pests in worm bins without disrupting the worm population itself.
Can I use Hypoaspis miles in rockwool or other soilless media?
Yes. H. miles is used across a range of growing media, including coco coir, peat moss, clay pebbles, and rockwool systems, as long as the medium stays moist and isn't waterlogged.
Do Hypoaspis miles need supplemental food?
No supplemental feeding is needed. They hunt naturally available prey in the soil and can fall back on algae and organic plant debris between pest availability, which is part of why they persist well even at low pest pressure.