theskyisthelimit99
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Giant White Grubs in the soil.. a problem? How to get rid of

I'm not sure if this is an issue for the plants or not, but I'm noticing a ton of white grubs in my soil this year.. maybe 1 every few feet, maybe more.. and they are pretty large in size. (I think they would be called a grub, unsure).

Does anyone know how harmful they are to the plants and if I should do something about it and if so what could be done?

I also have had a similar issue with above ground green grubs/worms on broccoli but i think the solution with that is to sprinkle DE on the broccoli leaves a few times before the head shows up.

Thanks in advance

theskyisthelimit99
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Re: Giant White Grubs in the soil.. a problem? How to get ri

I've spotted this smaller 2500 square foot container of St Gabriel that may work (reapply every 3 months for 2 years i think though)...
https://www.lowes.com/pd/St-Gabriel-Org ... ol/3083721

Or amazon has much larger 20lb bags for around $50..

A bit pricey though.

My garden is 25x40, so roughly 1000 square feet

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jal_ut
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Re: Giant White Grubs in the soil.. a problem? How to get ri

Relax. No use getting uptight about a grub unless it is actually damaging something.
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theskyisthelimit99
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Re: Giant White Grubs in the soil.. a problem? How to get ri

jal_ut wrote:Relax. No use getting uptight about a grub unless it is actually damaging something.
Oh I didnt realize they can be ok though.. i thought they tend to eat at the roots causing wilting?

bri80
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Re: Giant White Grubs in the soil.. a problem? How to get ri

theskyisthelimit99 wrote:
jal_ut wrote:Relax. No use getting uptight about a grub unless it is actually damaging something.
Oh I didnt realize they can be ok though.. i thought they tend to eat at the roots causing wilting?
It depends. A grub can be any number of species. You need to identify the actual species before you can determine if it is harmful or benign.

theskyisthelimit99
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Re: Giant White Grubs in the soil.. a problem? How to get ri

bri80 wrote:
theskyisthelimit99 wrote:
jal_ut wrote:Relax. No use getting uptight about a grub unless it is actually damaging something.
Oh I didnt realize they can be ok though.. i thought they tend to eat at the roots causing wilting?
It depends. A grub can be any number of species. You need to identify the actual species before you can determine if it is harmful or benign.
From the pictures i've seen, it certainly looks like Japanese beetle larvae (quite large too a few of them).

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rainbowgardener
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Re: Giant White Grubs in the soil.. a problem? How to get ri

Yeah that would have been my guess Japanese beetles.

The grubs don't do much damage that I can tell. Unless you have a major infestation of them or are maintaining a golf-course style lawn, you are not likely to notice damage. "Major infestation" would be around ten of them per square foot. Doesn't sound like that's what you have.

In June the grubs will hatch out into Japanese beetles. They are annoying and will chew up the leaves of all kinds of things. But again, unless you have serious infestation, all those chewed up leaves aren't likely to slow down your plants too much. To deal with them at this stage, spray the leaves of whatever they are eating with Neem oil. The adult beetles are only around for 6-8 weeks. Then they lay their eggs in the soil and die off.

The time to treat for the grubs is in Aug/September, when the new generation of grubs has hatched and they are still close to the surface. You can treat for the grubs with milky spore disease and/or beneficial nemetodes, both available commercially.
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dragonthumbs
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Re: Giant White Grubs in the soil.. a problem? How to get ri

I have dealt with a few of those myself, although they have not infested my garden or done any real damage, if anything, I pick them out of the soil after turning it and set them up on a plate for the bird to help themselves to! :p

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rainbowgardener
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Re: Giant White Grubs in the soil.. a problem? How to get ri

Oh wow! For three months I have had chickens and never thought to bring them the JB grubs I turned up while working the soil. -wall- (We need a face palm emoji!)
Twitter account I manage for local Sierra Club: https://twitter.com/CherokeeGroupSC Facebook page I manage for them: https://www.facebook.com/groups/65310596576/ Come and find me and lots of great information, inspiration

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applestar
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Re: Giant White Grubs in the soil.. a problem? How to get ri

Ah ha! I found the answer to my question in another post! :lol:
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