Nematodes 101: When & How to Apply 

They can start working in a few days but they do take a bit to kill them. If you have the product left or it's not to large of an area I do suggest a second application - even just to apply in a different angle to cover the spots you might have missed or hit lightly the first time.

@@willheeman5 What I have done in the past are 2 things: 1. I water my lawn for the next several days to ensure that the added watering helps the nematodes burrow into the ground. 2.I also add a second application about a week after the first application, and cut the grass before the second application to ensure that the nematodes do not have to overwork to burrow into the ground.

Yup, it can work in any soil you apply them to. The key is to manage expectations of how far down you need them to go to find the grubs. There are different nematodes in each mix you purchase - the one we sell (not available in Florida) has 3 kinds and one of them burrow in the deepest to get grubs that are 9" down. Most don't get that deep in the soil, usually 2-6" down. In a compost pile maybe it's different? Wherever you buy them I'd ask the retailer which nematodes are in the mix and judge from their response if they'd get down far enough in the raised beds to reach the grubs you are finding. Hope that helps! ~ Will

If you still have nematodes that are viable and have not expired, you can still apply them and put them on your garden beds. I would not suggest going out and purchasing any at this time because most grubs those nematodes target aren’t active now, they’re in their adult stage at the moment. Fall, like September-October, is going to be another good time to start applying those again.

Shouldn't hurt them. So long as you apply them and they're washed into the soil (off the grass blades) with watering or a natural rain, you should be fine.

Sorry to say that the strains of nematodes in this type of mix is very specific and will almost certainly download nothing to help minimize your problem. If you knew which type of flies they are and where they lay their eggs - you could apply something more specific to combat them. Mosquito Dunks, for example, are a product that works on fungus gnats, mosquitos and other insects that lay their eggs in damp or wet areas. Sorry, I just don’t think these nematodes will do anything for your problem.

@@willheeman5 Thank u

@@willheeman5 Im looking for flies larva control agent + technique, i already use dunks

Nope, as long as you can apply the nematodes and then water them in with enough water to penetrate through the mulch and into the soil, you're fine. They'll travel in the water as the delivery agent to get them into the soil where they can move around and start hunting the grubs.

You'll be able to find them at nearly all Independent Garden Centres - this brand from NIC are live nematodes which are fresh and have a best by date - they're raised here in Ontario. Hope that helps! :)

Sorry I missed this - if no rain is forecasted you can 100% just water them in. As long as you can drive any water droplets (that nematodes are in) from the blades of grass into the soil, you're good. Rain is just the most convenient, easiest way to do that - not the only way though!

When soil temperatures are above 10C you can apply - that means here in Ontario sometime in mid-late April until mid-May (when the grubs pupate and aren't vulnerable to nematodes). You can apply immediately after if you'd like. I'd suggest waiting a few days to 1-2 weeks (at most) to reapply. Do it in a different direction, if you walked the lawn east to west, go north to south - just so you hit each angle and catch any areas you might have missed. Wait too long and you miss your window. Beneficial to apply in the fall - for sure - grubs are smaller and nematodes are more effective then. Usually in September until early October is a good time for that fall application here in (SW) Ontario.

Lots of different nematodes, most are specialized to work against different prey. These nematodes will work on several bugs (June bugs, European chafer, Japanese beetle). For other insects you'd want to try to find other strains of nematodes!

In Ontario, it's far to early to apply nematodes now. I'd recommend waiting until September so you can ensure the baby grubs have been laid in the soil for nematodes to hunt down.

It’s possible to apply nematodes for flea control. The strain used for grub control (in this package for example) is completely different than the strain you’d apply to control fleas. They go after grubs specifically and wouldn’t affect fleas at all.

The biggest thing it could impact is how they get into the ground. Dusk is good, then they sun won't evaporate the water they're in as they get into the soil. That's the risk, that the water dries out before it gets to the ground.

@@willheeman5 I had not thought about that. It hasn’t rained in days and it isn’t expected to rain in a while. I can’t wait any longer as the grubs are doing some real damage to my grass. I will hit the “hottest” spots where the grass is turning yellow from the grubs eating the roots and hopefully I can save some of the grass before it’s too late. Thanks again.

Generally it's best applied annually. You can apply only when the problem is really bad (noticeable) but those who skip a year or more often find the problem comes back soon. Like most things, preventative treatments are a simple way to keep your lawn healthy and lush and not have any issues in the first place.

This applicator is one sold by Natural Insect Control, the same Ontario-based company we get our nematodes from. We don't offer them for sale online or for shipping, sorry. We do have the available at our greenhouse. If you're not local, you can find them at any place that also sells NIC nematodes.

@@willheeman5 great thanks!

This variety of nematode is pretty specific to certain pests but there are different strains and another strain does work on fleas. From our supplier this is the product they'd sell naturalinsectcontrol.com/product.php?id=000000449

Each package will have a best before date on it. If you're buying freshly brewed up nematodes it's usually 2-3 months. They're good as long as the date on the package says. :)

@@willheeman5 ok. Thanks. I need to check the package. I bought them a couple of months back but haven’t spread them yet. This will be my first time. I have grubs killing my St Augustine. Hopefully they are still alive. If not, I may have to order more and not wait as long to do what I should have done months ago. Thanks again.

Did you mean mow? If it's longer, yes. You'd want to avoid mowing the lawn until all the nematodes have slid down inside the water droplets into the soil. Ideally, you'd give them at least half a day to a day to do this.

@@HeemansLondon awesome. Thanks for the quick reply.

Yes, the soil temperature needs to be 50F or 10C. You can test it with a meat thermometer in the soil if you have one laying around.