Biological plant protection with nematodes can seem quite complex at first glance, but it is not so complicated if you spend a little time on it. Here we have collected some of the questions for you that we are asked again and again.

General questions about nematodes

What are nematodes?


Nematodes (nema: Greek = thread) are tiny, thread-like soil organisms approx. 0.5 mm long. In principle, besides insects they are one of the Earth's most species-rich multicellular organisms. They can be found in all conceivable habitats from the bottom of the sea to the peaks of the Himalayas – and even in insect larvae.

Among other nutrient sources, nematodes feed on plants, bacteria, fungi, their spores and even on other nematodes. Our nematodes are the natural enemy of insect larvae. Naturally highly specialised, they are exclusively able to use these larvae to feed on and reproduce.


Are nematodes harmful to my children or pets?

The nematodes sold by us only infect insects in the soil and as such are harmless to people and warm-blooded animals. The same also applies to plants; however, you should keep all plant protection agents away from children.

Are nematodes harmful to fish?

Our nematodes are also completely harmless to fish. You can apply our product right up to the pond edge. Here is a summary of a study conducted by Horst Bathon from the German Federal Biological Agency about the harm posed to people and animals:

Application poses no harm whatsoever to people, pets or other non-insects. While beneficial insects are sometimes infected, there is no discernible impact on the species composition (Bathon, H. 1996. Impact of entomopathogenic nematodes on non-target hosts. Biocontrol Science and Technology. 6. 421-434).

Can I apply an overdose of nematodes?

You can't apply too many nematodes. They are not harmful to people, animals or plants.

What happens to nematodes once they have killed all the pests?

The nematodes multiply within the pest while killing it. Once it is dead, their numbers decline dramatically. A small population can survive in other insects.

Why can't I apply the majority of nematode products the whole year round?

There is an optimal time of year for each type of treatment using nematodes as the pests are then in a vulnerable development phase (grubs, larvae, pupa). Treatment would be ineffective outside these times and therefore a waste of time and money.

Will nematodes survive the winter?

Yes, in small quantities; however, there will be insufficient numbers left to control pests the following year. As we only produce domestic nematode species, these are winter-hardy.

What is the powder made from?

The powder is a natural product made from calcareous shells (clay minerals). It is required for the nematodes to survive during transportation and to enable them to be stored for a short period.

Nematode application

Are packs covering over 100 m² available?

Yes, packs covering up to 1000 m² are available. They are only suitable for sports grounds and golf courses.

Can I also apply the product using a low-pressure backpack sprayer?

The nematodes should not be applied using a low-pressure backpack sprayer. It is better to use a watering can as you can stir the nematodes in-between applying them to prevent them sinking to the bottom, plus more water flows out of the watering can to water the nematodes into the soil.

Can I apply nematodes together with fertilisers?

Yes, that's fine; however, if possible we recommend applying fertilisers separately to avoid undue stress on nematodes.

Can I apply nematodes together with other plant protection agents?

In the majority of cases, yes; however, to be absolutely sure please follow our compatibility list.

Can I apply nematodes using a drip irrigation or overhead irrigation system?

Yes; however, in the case of overhead irrigation, you must factor in irrigation loss for the gaps between the pots. If using drip irrigation systems, it's worth using an additive so that the nematodes in the system stay in the suspension for as long as possible. Be sure to remove any filters and sieves from the watering systems. For details, please contact us or your plant protection service.

Can I buy a stock of nematodes?

No, because the nematodes can only be kept for a maximum of 6 weeks in the fridge.

Can I share a pack of nematodes with my neighbour?

Nematodes are microscopic organisms and as such they can't be seen in the powder with the naked eye. It is possible that the nematodes might be gathered in large concentrations in separate areas of the bag, but as you can't see them, the nematodes might not be distributed evenly if you share the pack. Therefore, we recommend buying two smaller packs or sharing the nematode broth directly after stirring.

Can I use any plant sprayer to apply the nematodes?

Yes, provided they have a stirrer and nozzle with a diameter of at least 0.8mm and a pressure lower than 5 bar. Be sure to remove all filters and sieves.

Can I use nematodes in organic farming?

Yes. Nematodes are beneficial animals and can be used in organic farming. The powder is natural and does not contain any preservatives.

Can nema-green® be used to control any grub?

It is excellent for controlling garden chafer grubs; however, similar-looking cockchafer and June beetle grubs can only be controlled within a narrow time frame using nema-green®. If you are unsure how to distinguish between these species of beetle, just send us a few examples.

How do I mix the nematodes?

Precise instructions are included with the product.

How do I work out how many nematodes I need?

The quantity you need depends on the area to be treated. Please see the product usage instructions. If you have any further questions, please just give us a call.

How long can I store nematodes for?

Nematodes can be stored at room temperature for a few hours without affecting their quality, and for up to six weeks when stored in a cool place at between 4 and 12 °C.

How long can nematodes remain in the spray bottle?

If the liquid is being moved continually, the nematodes can remain in the spray bottle for a few hours. However, do not keep them in there for longer than is necessary as the constant pumping causes them stress.

How long do nematodes remain effective in the soil?

Nematodes can survive for many months in the soil; however, they are continually decimated by their natural predators so their effectiveness declines increasingly. They are most effective in the first four weeks after application.

How often do I need to use nematodes?

To answer this question please check the corresponding product information.

Is the bacterium in the intestine of the nematodes harmful to people and animals?

No. The bacterium can only live in nematodes and the insects they infect. It is harmless to people and animals, and dies at body temperature.

The nematode powder looks different to how I remember!

The powder manufacturer uses a new process whereby the powder has a slightly different texture and colour. The effect is purely visual in nature and has no impact on the nematodes.

Any red colouring in the powder is due to the natural and harmless colouring produced during nematode production. The primarily white colour of the new powder now makes this more visible, which wasn't the case with the previous powder.

What do I need to bear in mind when applying nematodes?


Do not apply nematodes in direct sunlight as nematodes are sensitive to both drying out and UV rays. It's best to apply them during the evening or when cloudy. If the soil is dry, water it lightly beforehand. Watering in the nematodes after applying them makes it easier for them to bury into the soil.

As nematodes can only move in moist soil, the soil must be kept damp (but not wet) and must not be allowed to dry out in the weeks following application.


What does sensitive to UV light actually mean?

Long-term exposure to direct sunlight harms the nematodes, so they should be washed into the soil within 30 minutes. Apply to leaves preferably in the evening or under cloud cover.

Questions about nemaplus® Depot

How is nemaplus® Depot applied?


For professionals:

Place the capsules in the planting hole by hand when seeding or planting cuttings. Standard fertiliser spreader is suitable for automated application.

The capsules can also be mixed into the substrate before planting or seeding.


For Home gardeners:

Mix the capsules into the substrate before repotting or drill holes with your finger into the soil and place a capsule in it every 3 cm.


The packaging contains free water. Is that a problem?

No, a small amount of free water is normal. If you wish to store the product for a longer period, please read the product sheet in our downloads section.

Are the capsules compatible with chemical plant protection products and fertilisers?

Such substances have no effect on the capsules themselves.
Most such substances are almost not harmful to the nematodes. In order to be sure, we provide information on individual substances in our Compatibility List.

Can I use nemaplus® Depot in organic plant protection?

Yes, the capsules are made using only food-grade substances and are completely biodegradable.

How are the capsules comprised?

A nemaplus® depot capsule contains approximately 1,600 Steinernema feltiae nematodes in a water-oil emulsion encased in an alginate capsule.

How do the capsules work and how long do they work for?

In contrast to the powder-based product nemaplus® – in which the nematodes are applied using irrigation water and immediately enter the ground/substrate – the nematodes leave the capsules over time. After contact with the ground/substrate, the capsule becomes permeable after about one week and the nematodes gradually leave.
In this way, new nematodes enter the ground/substrate over several weeks to combat fungus gnat larvae.
This means that nemaplus® depot works for almost twice as long and can be used preventatively against fungus gnat larvae.

How is nemaplus® depot stored?

It is suitable for storage at 4-8°C until at least the printed expiration date. More detailed storage instructions can be found in the nemaplus® Depot download section.

When do the capsule remains completely disappear from the ground/substrate?

Depending on the ground/substrate, the capsules completely biodegrade after 4-6 weeks and are no longer visible. The nematodes will have all left by then and will be looking for harmful larvae.

Where is nemaplus® depot used?

Throughout the year in greenhouses for combating fungus gnat larvae in the ground/substrate.

Which substrates is nemaplus® depot suitable for use in?

The product is effective in all organic substrates. Sterilised substrates are NOT suitable.

Nematodes in drip irrigation systems

Are drip hoses or in-line / end drippers suitable or should it be better to use spray devices?

 Yes, they are suitable, but the last pots are always the problem, because the hose ends blindly, the flow rate in the hose is reduced after each dripper and at the end the flow rate is so low that the nematodes sink within the hose. Therefore, the last 3-4 drippers should not be used.

Instead, one should use a watering can to apply the nematodes for the last three plants


Can the nematodes be added with the usual fertilizer adding devices?

Yes, it can.
Only the filters and sieves need to be removed so that the nematodes do not get caught there and clog them.

Can you recommend any special dripping irrigation system?

The drippers usually have a diameter of 0.12 mm. This offers enough space for the max. width of 0.02-0.025 mm of the nematodes, which pass the drippers in a U-shape.

Do you have experience with the Gardena Micro-Drip System when used with nematodes?

No, we do not have any experience with the Gardena Micro-Drip System.

How can I check whether the nematodes are really coming out of the drippers?


  • Drip systems are very diverse: A visual inspection for nematodes from the dripper should be made
  • Hold the Petri dish under the dripper
  • Catch water from the dripper after 1m, 6 m, 12 m etc.
  • Fill each sample into a 20x20cm plastic bag, let the air out, close it with a zipper and place it on a black surface
  • Check for nematodes using a magnifying glass (10x amplification) and a flashlight (light source)
  • Or use binoculars if available


How does an optimal treatment with nematodes look like using a drip system / drip irrigation?

  • Proper pre-watering
  • Apply nematodes with sufficient water and without an interruption of the treatment
  • With high nematode dosage, the total amount should be distributed over several applications (dosage of 1 million nematodes / m² and higher)
  • Rinse with the same amount of water through the drippers


I really want to make sure that my dripping irrigation system is suitable for the application of nematodes!


If you are still not sure about it, you can, if possible, send us the nozzle/dripper.

Please add a small note to the package with your request and contact details. We will then contact you as quickly as possible.

e-nema GmbH
Klausdorfer Str. 28 – 36
24223 Schwentinental


Which additive do I need to improve the floating properties of the nematodes?

  • We made very good experiences with the additive CMC (thickener)
  • CMC should be stirred in well. Significantly better distribution of the nematodes over the hose length of the drip hose is achieved in this way.
  • A dosage of 1% in the Dosatron® is optimal so that a residual concentration in the drip tube of 0.016% CMC will be achieved.
  • After the nematode application, at least the same volume of water should be used for rinsing