Nematode Notions

Nematode Notions

While beneficial nematodes may be microscopic, they have a big impact on pest control and can achieve very visible results!

Nematodes are safe for pets, animals, biological control agents, and humans! If you are dealing with fungus gnats, thrips, or other soil dwelling pests like grubs or weevils, we recommend adding nematodes as a quick knockdown.

Life Cycle of the Beneficial Nematode

Infective juveniles are inoculated into packaging that is shipped to you!

These infective juveniles set out to find a new host to reproduce in. Preemptively saturating the root zone of plants you are treating can encourage their exploration. They infiltrate the pest through natural orifices and release symbiotic Xenorhabdus bacteria that kills the host within 24-48 hours. Infective juveniles mature into male or female adults and initiate breeding, using the pests’ resources to spawn future generations. These fresh infective juvenile nematodes will leave and scour the root zone for a new host and continue this cycle.

We offer nematode options from two main suppliers, Sierra Biological and BASF

While application rates may differ, we want you to know that these products are equally effective.

Application Rates:


-50 million per 1,000 Sq ft of soil surface

-250 million per 5,000 Sq ft of soil surface

-1-2 Billion per acre

Sierra Biological

-1 million per 1,000 sq ft of soil surface

-24 million per acre

Application rates will vary based on target pest, reach back to us at Sound Horticulture for specific guidelines based on soil depth of pest, media type, and other growing factors.

Nematodes can be applied as a drench, through spray equipment, or through irrigation systems. Nematodes are also compatible with many fertilizer and soil applied pesticides/fungicides. Compatibility has been tested with over 100 different chemical pesticides such as insecticides, fungicides, and herbicides.


PHOTO - Beneficial nematodes mixed with water and examined under a microscope. 

Reasons to choose each:

BASF nematodes are reared in vitro meaning within a culture dish. While this option may have higher application rates, they are still very effective and have extended shelf life when stored in refrigeration. These nematodes can be stored up to 6 weeks! These nematodes are shipped in trays of 50 million, 250 million, or 1,250 million. BASF is one of the largest producers in the world and have been in business for over 150 years! Check out a tour of their industrial facility here!

Sierra Biological uses in vivo production or as they say, “Mother Nature’s very own formula” This can be much more labor intensive but creates a wonderfully active and effective population. Wax worms arethe perfect rearing host to produce these nematodes for production and sale. These nematodes are shipped in a sponge that are pre-inoculated with infective juveniles, sizes range from 1 million, 6 million, and 24 million of either single species or blends. We also offer other formulations, please inquire for more details.

Beneficial Nematodes are used to control a variety of soil-dwelling pest. There are several types of nematodes, each specializing in the eradication of various pests.

Pests targeted by species:

Steinernema feltiae:

-Fungus gnats (Bradysia spp.)

-Western Flower Thrips (Frankliniella occidentalis)

Heterorhabditis bacteriophora:

-European chafer grub (Rhizotrogus majalis)

-Japanese beetle grub (Papillia japonica)

-Oriental beetle grub (Exomala orientalis)



Steinernema carposcapsae:

-Black vine weevil (Otiorhynchus sulcatus)

-Cranberry girdler (Chrysoteuchia topiaria)

-Shore Fly (Scatella stagnalis)

-Cut worms (Agrostis sp.)

-Army worms (Spodeptera frugiperda)

-Wood borers (Buprestidae sp.)

Steinernema krassei:

-Cold tolerant species (Optimal range 41-86ºF)

-Black vine weevil (Otiorhynchus sulcatus)


Application Tips:

Best Practices

• Use fresh nematodes, they can be stored in the refrigerator for multiple weeks but have the highest efficacy when fresh. Examine under a microscope and look for wiggly live worms. Dead nematodes will be straight as a pin.

• Apply early in the morning or in the evening as nematodes are susceptible to desiccation and UV light. When ready to apply, bring nematodes out of refrigeration and allow them to warm up in room temperature for 20 minutes. Always use room temperature water to mix the nematodes.

• Apply to already moist soil and keep the soil moist for several days after application. Soil should be 54-86ºF.

Remove all filters if using sprayer or irrigation and keep pressure below 300 psi.

Once mixed, use within a couple hours and keep agitated as nematodes will sink to the bottom. Try to only make enough solution to hit every plant you are trying to treat. Nematodes left in reservoirs will die as they are soil dwelling creatures, not aquatic. They need the water to reanimate from their packaged state.

Do not oversaturate pots, the nematodes will flow through the pot and exit the drain holes.

Watering By Hand (Home growers)

1. Mix a stock solution. Add 2 gallons of clean, cool water to a five-gallon bucket and mix in nematodes. Allow five minutes to disperse. Continue to stir throughout the application as they will sink to the bottom.

2. Add 1 cup of stock solution to a 2 gallon watering bucket. Water plants to saturate the potting medium 2″ deep. This will fill 32 buckets.

3. Apply approximately 3 oz/4 inch pot and 8 oz/ 1 gallon pot. 



Steinernema feltiae nematode sponge

Steinernema feltiae (SF) is unique in maintaining infectivity in soil temperatures as low as 50ºF (10º C). SF has a foraging strategy in between “ambush” and “cruiser” and is effective against immature dipterous insects including mushroom flies, fungus gnats, thrips, and tipulids as well as some lepidopterous larvae.


Heterorhabditis bacteriophora (HB) nematode sponge

Heterorhabditis bacteriophora (Hb) is a warm temperature nematode performing best above 70ºF (20ºF) soil. Hb is among the most ecomonically important entomopathogenic nematodes that possess considerable versatility, attacking lepidopterous and coleopterous insect larvae among other insects. This “cruiser” species appears quite useful against root weevils, particularly black vine weevil where it has provided consistently excellent results.


Steinernema carpocapsae (SC)

Steinernema carpocapsae (Sc) is the most studied of all entomopathogenic nematodes and most effective between 72-82ºF (22-28ºC). They can also survive for several months in room-temperature soil. Sc is particularly effective against lepidopterous larvae, including various armyworms, cutworms, webworms, girdlers, some weevils, and wood-borers. A classic sit-and-wait or “ambush” forager, it stands on its tail in an upright position near the soil surface and attaches to passing hosts. Therefore, Sc is especially effective against highly mobile surface-adapted insects.

BASF NEMAforce SF tray

Beneficial nematodes attack, invade and kill targeted pests in the easily applied form of NemaForce SF Biosolutions by BASF.

Comments on this post (2)

  • May 29, 2024

    The best nematodes for cooler temps that are effective for beetle larvae are Steinernema kraussei. They are active between 40 to 86F You can read more on our tech sheet, best of luck!

    — Elaine

  • May 29, 2024

    Chafer beetle grubs are bringing the ravens who tear up the lawn
    It’s still pretty cool here, daytime temps about 45-50
    I read there’s nematodes for these, how many per 1000 ft?

    — David Lendrum

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