This year, I had a really bad infestation of Japanese beetles, so I recently applied milky spore. I used it many years ago with success back when I lived in NJ. I used the concentrate version that you apply every 4 ft in a grid pattern. I used an old tea spoon to apply it. You won't see an immediate improvement as the spores need the dying grubs to spread them, so it may take a couple of years to see an improvement.

The advantage of milky spore is that it lasts many years. Predatory nematodes need to be re-applied every year.

 

Milky spore is effective, but can take three years of active application to achieve a control result. The Andersons now make an organic OMRI certified grub control that, I believe, protects against 12 different types of grubs. I haven't personally used it and don't have a grub issue, however if it came to it I would want to try this product.

 

Yes, I have done them all. I have seen a marked decline over a 2 year period. I am talking from 100s of them on 1 plant to 10.

You need to add Bag a bug to the list as well. the work brilliantly.

 

Bag a bug?

 

Milky spore is effective, but can take three years of active application to achieve a control result. The Andersons now make an organic OMRI certified grub control that, I believe, protects against 12 different types of grubs. I haven't personally used it and don't have a grub issue, however if it came to it I would want to try this product.

This is BT. You can get liquid here https://www.domyown.com/monterey-bt-insecticide-p-2821.html?sub_id=11262

 

@Factor thank you, both have Bacillus Thuringiensis. Any idea what the strain SDS-502 vs SA-12 solids might indicate?

 

@Factor thank you, both have Bacillus Thuringiensis. Any idea what the strain SDS-502 vs SA-12 solids might indicate?

http://npic.orst.edu/factsheets/btrefs.html

http://npic.orst.edu/factsheets/btgen.html

I believe it related to what strain of the Bacteria BT
https://en.wikipedia.org/wiki/Strain_(biology)

BTW I love your State. Maine is awesome.