BASF Agricultural Solutions UK

Nemasys H


Nemasys® H contains the beneficial nematode Heterorhabditis bacteriophora and effectively targets the black vine weevil (Otiorhynchus sulcatus) present in soil or container-grown crops.


  • Fast and effective natural control.
  • The most robust and efficacious nematode product on the market for vine weevil control.
  • Control achieved at all times when the pest larvae are active.
  • No pest resistance problems.
  • Gives high levels of control between 12°C - 30°C.
  • Safe to crops, users and the environment.

Product Profile

Active ingredient(s)Nematodes: species Heterohabditis bacteriophora
Pack size50 million or 250 million
CropsSoil or container-grown crops
Pest activityLarvae of the black vine weevil (Otiorhynchus sulcatus)
Rate of application500,000 – 1,000,000 per m2 depending on crop/situation or 25,000 per plant for strawberry (see label)
Application area treated100 m2 or 2,000 strawberry plants (50 million pack size); 500 m2 or 10,000 plants (250 million pack size)
VolumeVaries with pot volume (see label)
Soil temperatureBetween 12OC and 30OC
Application methodSoil drench (via dosing unit and drip irrigation or knapsack sprayer)
Application adviceApply when the soil/growing medium is moist Avoid applications in direct sunlight, evening applications are best
Do not exceed 300 psi/20 bar/2000 kPa pump pressure
Nozzle aperture should be greater than 0.5 mm
Suitable nozzles should produce a course spray at the intended application pressure
Make up the stock solution and mix thoroughly to ensure that the nematodes are well dispersed
PrecautionsUpon receipt, use immediately or store in a refrigerator at 5OC
Do not use product if past expiry date or incorrectly stored (do not freeze)
Use entire packet at one time, do not store diluted product

How do Nematodes work?

Nemasys® H is applied to the growing medium or soil where the nematodes seek out the vine weevil larvae in the root zone of the plants under attack.

  • After application the nematodes enter natural body openings or penetrate the larval cuticle directly.
  • Once inside, they release bacteria that stops the larva from feeding, quickly killing it.
  • They do not stop there. The nematodes reproduce inside the dead pest.
  • They release a new generation of hungry nematodes, which disperse to hunt down further pests.
  • When nematodes can no longer find a host pest, they will die back to their original numbers. The more pests there are, the better nematodes perform.
  • Nemasys H persists for approximately four weeks.

Vine weevil plant damage

Black vine weevil has been found to be able to feed on over 140 different plant species. Plant damage can be caused in a number of ways, including adults feeding on leaves (notching of leaf margins) and larvae feeding on the roots, which limits growth and can cause plant death.

 Technical Services Hotline +44 845 602 2553

Technical Services Hotline +44 845 602 2553

Technical Services Hotline

Nemaslug® Biological Slug Killer

Nemaslug® Biological Slug Killer

Nemaslug® controls all common species of small to medium sized slugs. Start your control early and you will be able to target the young slugs growing under the ground before they do any damage.

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Compatibility list

Click here to take a look at our latest compatbility list

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