Nematodes are microscopic organisms that are naturally occurring and present in the soil. They are harmless to wildlife, pets and humans so you may use your lawn immediately after applying. Nematodes die off when the grub population in your soil is reduced.
Nematodes are best used as a preventative application to control newly hatched larvae so the best time to apply them is in early spring and in late August to early October. They infect grubs within 2 days of application and kill them within 14 days. Therefore grubs die approximately 16 days after the nematodes have been applied. Nematodes will not kill the entire grub population in your lawn, but will reduce it drastically.
Nematodes are effective up to 4 days without refrigeration. Live nematodes should have no smell to them; however your nematodes may be dead if you notice a distinctive dead fish smell.
It is ideal to apply Nematodes in early spring and/or from the end of August to October.
should be applied to very moist soil (the will die if applied to dry soil). It is recommended that you water your lawn well BEFORE applying nematodes. This also drives the grubs closer to the surface which makes it easier for the nematodes to reach them.
Nematodes should not be applied on bright sunny days, as UV light will kill them. It is recommended that you apply them early or late in the day, or on an overcast day. Ideally, apply the Nematodes on a rainy day, as it will aid in the watering in of the Nematodes.
Nematodes should be sprayed into the lawn using a sprayer designed specifically for nematode application. For the nematodes to work effectively, it is essential to water the soil as soon as possible as the water helps them to penetrate further into the soil, where the grubs live.
Note. Having your lawn aerated before applying nematodes will aid in the movement of the grubs into the root zone of your lawn.Source: www.paulsgardencentre.com