No more white worms!


Bioprotec Nematode is the natural solution for controlling root zone pests in lawns, flower beds, and vegetable gardens, such as white worms (beetles and chafer beetles) and grey worms. It contains two species of nematodes Heterorhabditis bacteriophora and Steinernema carpocapsae for superior effectiveness. Approved for organic farming.

The Bioprotec nematode sprayer is specially designed for use with these microorganisms. Unlike other sprayers, it does not have a filter, allowing for an even distribution of nematodes throughout your property.


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Explanation Video

Using Nematodes to Counter White Grubs on Your Lawn

White Grubs

Identification, Treatment, and Prevention


Your lawn has been ravaged by skunks, crows, or raccoons. White grubs have likely taken up residence in your lawn last summer and caused damage much larger than their size. But what is this insect and how can you control it?



A white worm, that's what it looks like! It lives in the soil, not far from the roots of your lawn. It is present in the majority of regions in Quebec, including the Outaouais and Quebec City regions, including Montreal, the Monteregie, the Mauricie, the Laurentians, Lanaudiere, the Eastern Townships and Central Quebec.



First Sign

The first sign of white worms on your property is usually a withering of the lawn in the fall, despite adequate watering. You may also notice that the grass easily detaches in patches. Some predators may be attracted to the larvae and cause even more damage by digging in the soil (skunks, raccoons, crows, etc).



The White Grub Cycle

There are several types of white grubs in Quebec. The white grub is the larval stage of several beetles (insects), including the Japanese beetle, the European chafer, and the common chafer. The European chafer and Japanese beetle have a one-year cycle. They lay their eggs in the soil at the beginning of summer. The eggs then develop into larvae, which feed on the roots of the grass throughout the rest of the summer, fall, and following spring. They then transform into adults at the beginning of the next summer, and the cycle starts again! For the common chafer, the larval stage is present in the soil for about 2 years.

The Fight Against White Worms

With the update of the pesticide management code, the solutions for controlling white grubs are reduced. Since March 2019, products containing imidacloprid are banned in Quebec (use and sale). You and lawn maintenance professionals can no longer apply Merit this year. 

A natural and affordable solution is available to you: nematodes. What are nematodes? They are microscopic worms that parasitize white grubs. They penetrate inside the larvae, causing their death and reproducing inside them. Thousands of new nematodes come out in search of new larvae. We thus observe a snowball effect since the cycle is rapid (ten days per cycle). To achieve effective control, certain conditions must be met.


Nematodes can control the larval stages of several other insects (such as moths and cutworms), both in lawns and in vegetable gardens and flower beds.


The Bioprotec - step by step approach

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


Application method


The 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 the final step. You can use a sprayer that you already have at home, or preferably use one designed for this purpose. It is important to make sure that the sprayer does not have a filter, as this would prevent the evenly distribution of nematodes on your property. Follow the instructions for application.

  • When the population of white worms is very high, up to 3 applications may be necessary to control them in your lawn. However, the best time to apply them is at the end of July or the beginning of August. Treatment on young larvae is much more effective.

    Applying treatment during this period allows the nematode population to multiply in the soil by completing multiple cycles of infecting white worm larvae. It is recommended to reapply the nematodes at the beginning of autumn (September) and in the spring when the population of white worms is very high.

    Keep the nematodes refrigerated until use. As they are living organisms, an expiry date is listed on the packaging.

  • The soil temperature should be between 12° and 28°C.

  • Water the lawn before and immediately after application (unless applied in the rain!).

  • Spray the nematodes on the lawn in the late afternoon.

  • Keep the lawn moist for 7 days after application. The moisture in the soil will allow the nematodes to move and parasitize the white worms. Maintaining slightly longer grass will reduce your need for water to keep the soil moist.

For maximum efficiency, there should be three application periods:
Early spring, mid-summer, and early fall




Treatment during the summer, at the end of July and beginning of August, is crucial for effectively reducing white worm populations. The treatment should be repeated in September and spring when infestations are high. The effectiveness depends on the timing and conditions of application. To reduce water consumption, wait for a period of rain. When all the best conditions are met, efficacy can reach 80-90%. However, the fight against white worms must be carried out every year as new eggs will be laid and the adult is very mobile.

Other favorable conditions in the fight against white worms

  • Minimize outdoor lighting during the adults' activity period (early to mid-summer) to avoid attracting them.

  • Maintain good lawn vigor through proper fertilization.

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

  • Maintain a higher mowing height during the egg-laying period to maintain soil moisture, which is unfavorable for the eggs.

Fighting Against White Grubs and Japanese Beetles in Their Adult Stage


Let's start with some good news! Adult white grubs do not cause damage to plants. However, the situation is different for the Japanese beetle, which feeds on the leaves and flowers of over 400 plant species, including fruit trees, vegetables, and ornamental plants. Here are the steps to controlling them: 

  • In the morning, take a walk in your garden with a bucket of soapy water. Use your hand to knock Japanese beetles into the bucket and cover it with a lid. 

  • If Japanese beetles are very numerous, you can set up traps, which are available at gardening stores. Place the trap away from sensitive plants and regularly empty it into a bucket of soapy water. Note: Do not use this trap if there are no insects present to avoid attracting them.