Phytoseiulus Persimilis Slow-Release Prevention Sachets
10% off your first 4 orders, then 50% off every order after.
Heads up—this is just an estimate. We only ship when the bugs are happy and ready to travel (Mon–Thurs). If a colony needs a beat to peak, or we're propagating a fresh batch, your order might hold up to a week. Treatment bottles jump the line when you've got an active infestation.
Phytoseiulus Persimilis Slow-Release Prevention Sachets
At A Glance
Targeted Biological Spider Mite Prevention
Stop the Outbreak Before It Starts.
Spider mites (Tetranychus spp.) are notoriously stealthy. By the time you spot the webbing or the characteristic stippling on your leaves, the colony has already established itself.
Phytoseiulus persimilis is the gold standard in biological control—an aggressive, obligate predator that feeds exclusively on spider mites. Our slow-release sachets transform this active hunter into a preventative shield, delivering a rolling population of predators to protect your high-value canopy.
How It Works: The Specialist Advantage
Unlike generalist predatory mites that might wander off to eat pollen or thrips, P. persimilis has a single biological directive: Hunt spider mites.
Each sachet functions as a miniature rearing system, releasing a controlled wave of eggs, juveniles, and adults over 2–4 weeks. This creates a standing army of defenders right where you need them—on the plant stems and foliage—preventing migrating mites from establishing a foothold.
Targeted Pests
These sachets are engineered specifically for web-spinning mites of the Tetranychus genus.
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Two-Spotted Spider Mite (Tetranychus urticae): Primary Target (High Efficacy)
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Carmine Red Mite (Tetranychus cinnabarinus): Effective at all life stages
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Pacific Spider Mite (Tetranychus pacificus): Strong suppression
Note: As long as the mite species spins webs, P. persimilis will likely target it. It ignores other pests like Thrips or Aphids.
Is P. persimilis Right for Your Environment?
Phytoseiulus is a high-performance predator that thrives in specific conditions. Use this guide to determine if it fits your IPM strategy.
Ideal Use Case:
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Pest: You are dealing exclusively with Spider Mites.
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Climate: Warm & Humid (68–85°F / 60%+ RH).
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Strategy: Preventative "insurance" for high-value crops.
Avoid Use If:
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Pest: You need to control Thrips, Broad Mites, or Russet Mites (Use A. swirskii or A. andersoni instead).
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Climate: Cool, dry, or drastically fluctuating environments.
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Strategy: You are treating a massive, established infestation (Use P. persimilis in bottles for immediate knockdown).
Why Choose Sachets Over Bottles?
For growers managing greenhouses, nurseries, or indoor grow tents, sachets offer a "set it and forget it" solution.
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Sustained Release: Provides continuous protection for up to 4 weeks, bridging the gap between manual sprays.
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Precision Deployment: Hang directly on the plant to minimize travel time for the predators.
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Clean Application: No carrier material mess on your foliage; ideal for ornamental and tissue culture acclimation.
Application Instructions
For Best Results: Hang High, Keep Dry. P. persimilis naturally moves upward toward heat and light, which is also where spider mites congregate.
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Preventative Rate: 1 sachet every 3–6 feet (roughly every other plant).
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Hot Spot/High Value: 1 sachet per plant.
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Placement: Hang on the main stem or a branch near the canopy.
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Care: Avoid directly misting the sachet. Water damages the rearing media inside.
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Frequency: Replace every 2–4 weeks during active pest seasons.
Frequently Asked Questions
Are P. persimilis sachets safe for pets and people? Yes. These are 100% non-toxic and safe for humans, pets, and pollinators. There is no re-entry interval required after application.
Can I use these sachets on flowering plants? Absolutely. Because the mites are contained in the sachet and only exit to hunt, there is no loose bran or vermiculite to dirty your flowers or resin.
How do I store the sachets if I can't hang them immediately? Phytoseiulus persimilis is a live product. We recommend hanging immediately upon arrival. If necessary, store at 45–55°F for a maximum of 24 hours. Do not freeze or store in a refrigerator with a dehumidifier (like a standard kitchen fridge).
Shipping & Guarantee
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Freshness: Ships via 2-Day Air to ensure viability.
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Live Arrival Guarantee: We stand by the quality of our microbiology.
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Support: Questions about your specific crop? Contact us for a tailored IPM consultation.
Target Pests
Environmental Needs
Selection Guide
How to Use
How They're Shipped
Hang them up, then wait.
How to deploy your sachets, and how to read the results over the next few weeks. Sachets are prevention — a slow-release nursery that ramps up over weeks, not a quick knockdown for an active outbreak.
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Open the box right away
Bring the package indoors as soon as it arrives. Don't leave it on a hot porch, in a cold mailbox, or in direct sun. If you can't deploy immediately, set the sachets somewhere room-temperature (60–75°F) and out of direct light — they'll keep for a day or two.
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02
Don't open the sachet
Each sachet is a self-contained breeding colony. The mites and their food source live inside; they emerge gradually through a small exit hole on the breathable face. Cutting the sachet open ends the slow release and dumps the colony all at once. Keep them sealed.
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03
Hang or place near the plant
Hook each sachet on a sturdy branch, hang from a stake, or set near the base of the plant — out of direct sun and away from anywhere it'll get watered. Mites travel from the sachet onto the plant on their own. One sachet protects roughly 2–3 feet of canopy; see the product description for exact spacing.
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Leave them alone for 4–6 weeks
Predator emergence ramps up over the first two weeks, peaks around weeks three to four, and tapers off through week six. You won't see the predators (they're smaller than a grain of salt), and an "empty-looking" sachet at week one means nothing. The real signal is what isn't happening — pests not establishing on protected plants.
Something visibly wrong on arrival?
Sachets that arrived torn, soaked, or with a sour smell — take a photo and email info@fgmnnursery.com within 24 hours of delivery with your order number. We'll replace or refund without question.
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FAQ
What is your Live Delivery Guarantee?
We guarantee that your beneficial insects will arrive healthy and ready to work. Because we are shipping live organisms, we use packaging and expedited shipping to ensure their safety. In the rare event that your order is compromised during transit, please take a photo of the package and contact us within 24 hours of delivery so we can make it right.
I have a minor spider mite infestation. Are sachets enough?
I don’t see anything moving inside the sachet. Are they dead?
Why use sachets instead of just spraying?
Will they stay on the plant if there are no spider mites yet?
Are these safe for flowering or "sticky" plants?
Can I use these with other predatory mites?
Help! I'm overwhelmed
Yeah, it's a lot the first time you're using predatory mites. Please email us at info@fgmnnursery.com and we'll be happy to help!
I don’t see anything moving in my bottle or sachet. Does that mean they’re dead?
Not at all! In fact, go ahead and deploy them.
Predatory mites are microscopic (often less than 0.5mm) and naturally blend into their carrier medium (bran or vermiculite).
- For Bottles: The mites often huddle in the center of the bottle for insulation during transit.
- For Sachets: These are "slow-release" nurseries. The mites stay tucked deep inside the breeding media and emerge one by one over 2–4 weeks. Seeing an "empty-looking" sachet or bottle is not proof of a loss; it is simply how they are packaged for maximum survival.
Got my whole army in there hopefully it clears up anything and keeps my plants safe
Arrived on time and right to my front door 👌 $40 a month to not have spider mites eating my plants is something I can live with 😎
Hi!
Thank you so much! The review is showing as a 1 star, if there’s anything we can do to make your experience better, please don’t be afraid to reach out. :)
I released the predators throughout my plant collection and was ridiculously excited when I actually spotted one crawling around near the new growth doing its little predator business. Everything arrived well packaged and the whole process was super easy. FGMN Nursery has officially convinced me that outsourcing pest control to microscopic employees is the way to go.
Hi Amanda, we're thrilled to hear you're pleased with your new hires! ;) Thank you for the support.
Perfect, fast, as described, time will tell!!
Thank you! If you have any questions you know where we are. :)
Great
The first release didnt serm to do much after we had a brief cold spell during thst period. This second release seems to be making a big difference while not completely controlling the pests yet. May need a 3rd release. Definitely worth it.
I only received 9 of the 10 Satchets but the free addition of ladybugs was a nice surprise. I’ve had them for about 4 days and I’m still waiting for the mites to emerge, hoping to see some activity soon.
Hi there,
Thank you for your feedback and for giving our sachets a try! Have you reached out to us yet at info@fgmnnursery.com about the missing sachet? If not, please do so they can look into sending you one or offering store credit.
Just as a quick note on how sachets work: each one contains a mix of mite eggs and immature life stages. Rather than releasing a large burst all at once, they gradually produce and release a few adult predators each day (usually 2–3 per night). This slow and steady release helps establish a consistent predator presence in your plants, providing protection over the full 2–4 week period. Because of this, it can take a little time before you see visible activity.
We appreciate your order and are here if you have any questions!
Packaged well and received early.
The ordering process start to finish was easy. I placed the packets, and waiting to see how the trees do. If it will save my trees I will order more.
Excited to see how they work!
You're going to love them! Thank you for shopping with us!
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