Targets white grubs

Technical information

Treatment calendar

White grub control

Bioprotec Nem is a natural solution for the control of root pests in lawns, flower beds and vegetable gardens such white grubs (June beetles, European chafers and Japanese beetles) and cutworms. Made with two species of nematodes Heterorhabditis bacteriophora and Steinernema carpocapsae for greater efficacy. Approved for organic culture. More information.

A specially designed Nematode sprayer is also available. The use of the Bioprotec Nematode Sprayer will ensure a better distribution of the nematodes on your lawn, while preventing clogging inside the sprayer.


An explanatory video on the use of nematodes to fight white grubs on your lawn

Click here to watch the video

White grubs - Identification, treatment and prevention

Your lawn has been ravaged by skunks, crows or raccoons. White grubs may have established a home in your lawn the previous summer and have caused much greater damage than their size. But what is this insect and how can you control it?


A white grub, it looks like this! It lives in the soil, not far from the roots of your lawn. It is present in the majority of most regions in Quebec as well as the Maritimes and Ontario.

The first sign of the presence of white grubs on your land is usually a decline in Autumn of the lawn despite proper watering. It can also be observed that the grass is easily detached in patches. Some predators will be attracted to the larvae and will cause even greater damage by digging the soil (skunks, raccoon, crow, etc.).

The white grub cycle

There are many types of white grubs and populations may differ from region to region. The white grub is the larval stage of several beetles (insects), including Japanese beetle, European chafer and June beetle. European chafer or Japanese beetle have a 1 year cycle. They lay their eggs in the ground early summer. Eggs become larvae that feed on the roots of the grass during the rest of the summer and the following fall and spring. They turn into adults early the following summer, and the cycle starts again! For the June beetle, the larval stage is present in the soil for approximately 2 years.

The fight against white grubs

With the pesticide regulation update in Quebec, the solutions to control white grubs are reduced. Since March 2019, products containing imidacloprid have been banned for use and sale. Domestic users and lawn care professionals can no longer apply Merit this year in Quebec. This product has already been banned in Ontario for a few years.

A natural and affordable solution is available to you: nematodes. What are nematodes? These are microscopic worms that parasitize white grubs. They enter the larvae, cause death and reproduce inside of them. Thousands of new nematodes emerge in search of new larvae. There is thus a snowball effect since the cycle is fast (ten days per cycle). To reach good control, certain conditions must be respected.

Nematodes can control larval stages of several other insects (webworms and cutworms) in the lawn, garden and flowerbeds.

Bioprotec : Use direction

There are some nematode products on the market. Choose refrigerated products containing live nematodes, such as Bioprotec. In addition, the use of nematodes is approved for organic agriculture.

  • When white grubs population is considerable, up to 3 applications may be needed to control white grubs in your lawn. Nevertheless, the best time to apply them is at the end of July-early August. A treatment performed on young larvae is much more effective. Treatment at this time allows the nematode population to multiply in the soil by completing several cycles of infection with larvae.

    It is recommended that the nematodes be re-applied in early fall (September) and in the spring when populations of white grubs are very high. Keep the nematodes in the refrigerator until ready for use. Since they are living organisms, an expiration date is written on the package.

  • Soil temperature must be between 12° and 28°C.

  • Water the lawn before application and immediately after (unless applied when it’s raining!).

  • Spray nematodes on the lawn at the end of the day.

  • Keep the lawn moist for 7 days after application. Soil moisture will allow nematodes to move and parasitize white grubs. Maintaining a higher cutting height will reduce your water requirements to keep your soil moist.

Method of application

Bioprotec nematodes are sold in a sponge. Keep the packaging in the refrigerator (between 4° and 12°C) until use. You will need a sprayer for application. You can use a sprayer that you already have at home or preferably the one designed for this purpose. It is important to ensure that the sprayer does not have a filter which would prevent the homogenous spread of nematodes on your lawn. Follow the instructions for the application.

For maximum efficiency, it takes three periods of application: Early spring, mid-summer and early fall


Summer treatment in late July / early August is very important to effectively reduce white grub populations. The treatment should be repeated in September and spring when infestations are high. Efficacy depends on the timing and conditions of the application. To reduce water uptake, wait for a rainy period. When all the best conditions are met, efficiency can reach 80-90%. Nevertheless, the fight against grubs must be done every year since new eggs will be laid and the adults are very mobile.

Other favorable conditions in the fight against white grubs

  • Minimize outdoor lighting during the adult activity period (early /middle of summer) to avoid attracting them.

  • Maintain good turf vigor by adequate fertilization.

  • Use organic fertilizers during the summer period to support soil biodiversity.

  • Maintain a higher cutting height of the turf during the laying period to maintain soil moisture that is unfavorable for eggs.

The fight against June beetles, European Chafer and Japanese beetles

Let's start with the good news! Adult June beetle and European Chafer do not cause plant damage. The situation is different for the Japanese beetle that feed on the leaves and flowers of more than 400 species of plants; fruit trees, vegetable and ornamental plants. To control them, here are the steps to follow:

  • In the morning, take a walk in your garden with a bucket of soapy water. With your hand, drop the Japanese beetles into your bucket and close the lid.

  • If Japanese beetles are numerous, you can install traps available in garden centers. Place the trap away from sensitive plants and empty it regularly in a bucket with soapy water. Warning! It is suggested not to use this trap if insects are not present to avoid attracting them.