Asica
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Keeping cutworms from going to the raised garden

I have two keyhole gardens. It is infested with cutworms or grubs or both. I look at the pictures and compare and I would say grubs. I have also seen beetle go under the soil. However, I have seen plants being cut. Either way Raccoons love eating them, so I have no Fall garden for that reason. The Spring is coming and I am planning how to deal with it. Raccoons are smart and visit me once a week. Now, I need to trick them. Getting rid off them is going to be impossible in LA.

So my plan is to take out all the soil from the keyhole garden. Put black weed barrier on the bottom of the keyhole garden. I am hoping and asking if this will stop cutworms and grubs from coming through the bottom. If not that what will?
Then, I will rebuild the keyhole garden and build a wire fence around the garden.
Before I put the fence, I was thinking about leaving it open so raccoons can visit and see that there is no worms inside. What do you think about my plan?

imafan26
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Cutworms are the larvae from butterflies and grubs could be from anything from beetles to moths. A collar around the young seedlings will help thwart the cutworms, but to keep the butterflies and moths out you would have to have netting over the top. Grubs are a seasonal problem and one I don't really have as my garden patrol (lizards and skinks and a few insect eating birds) take care of most of the beetles and caterpillars that show up in the garden. I don't have mongoose in my yard, but I do have greenhouse frogs.

Tilling the soil a couple of weeks before planting will help expose grubs so you can hand pick any that you see. Grubs are more of a problem during the warmer months of the year and solarization around July-August will help with that. Other than that, you can try to attract predators like parasitic wasps, lizards, and insect eating birds. The racoons probably are attracted to the grubs in the garden. Cultivating and hand picking would be the other options. If you soak the garden really well in the evening the grubs will rise closer to the surface. If you have a lawn, it may be the biggest source of the grubs and you could use some kind of grub control in the lawn to reduce the population. For myself, I eliminated most of the lawn and only have a little left and my grass is not particularly tasty to lawn pests so it is not really a problem. I have emerald zoysia and St. Augustine. Chinch bugs do go after the St. Augustine, but the cattle egret and mynahs go after the bugs.

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applestar
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Yeah, I don't think they are coming UP from deep in the soil. They should be in the top few inches of the soil and, like imafan said, turning the upper layer of the soil should be enough to expose them. I suppose you could try sifting the soil if you want to find them yourself.

Are you sure the raccoons are eating the grubs? Don't you have compost in the middle of the keyhole garden? But Rainbowgardener has often said raccoons could be kept out by using deer netting secured along a raised bed frame and cinched or gathered and tied closed at the top. (Raccoons can climb over an open wire fence)

Once the beds are netted closed, it will keep birds out, too. It would really help to figure out what kind of larvae you have in the soil. If raccoons are really eating the grubs, then you will need some other predators in your Garden Patrol to control them.

"Beetles going under the soil" could be ground beetles couldn't it? They are predators. If you are lucky, you might also have predatory wasps in your garden that specialize by laying eggs on grubs. Maybe you might consider getting predatory/beneficial nematodes before the weather gets too hot to apply them.

Asica
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Location: California (Los Angeles)

Thank you for the replies.
I will dig for the worms tomorrow and take a picture. In my one keyhole garden I can find around 20 worms. I have digged for them several times, but they keep on coming back.
I have no grass in my yard. I had year ago, but I took all of it out.
The keyhole garden has compost in the middle, but I keep cover on it.
The raccoons, I have actually seen. There are inprints in the soil. They were even taking lid off Olla watering stats them to take a sip of water. I also see that they dig in neighbors' grass.
When I look for worms, I notice they are mostly around the compost basket and next to the wall of the keyhole garden. The keyhole garden is made of brick. When I was taking the grass out from my yard, I kept finding the same worms. Now I do not find them anywhere else besides the keyhole garden.
In the morning, I will take some pictures to better present my problem.
I like the idea of the net. I was thinking on building something like that as long as raccoons will not go through it.

Asica
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Location: California (Los Angeles)

20170128_124859.jpg

Asica
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Posts: 240
Joined: Fri Sep 25, 2015 1:11 am
Location: California (Los Angeles)

So those are the worms that I find. Today it was much less of them. I had to dig for them. Found them on the bottom of the keyhole garden, one foot deep.

SQWIB
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SQWIB
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Asica wrote:So those are the worms that I find. Today it was much less of them. I had to dig for them. Found them on the bottom of the keyhole garden, one foot deep.
Yeah, I believe they're grubs

Asica
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SQWIB thank you for the link. I found it very useful. I think, I have a plan now.

ButterflyLady29
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Milky spore works only on Japanese beetle grubs. June bug grubs look very much like Japanese beetle grubs, the only difference is the way the hairs line up on the very back end of the grub. But milky spore won't work on June bug grubs, according to the package. I had them real bad in my containers that had a sandy mixture in them. The containers without sand didn't have grubs. I had to dump the containers and sift through all the soil to get all the grubs out. I don't know how to get rid of them other than hand digging and drowning them in soapy water.

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Gary350
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Get some moles for your yard they EAT, cut worms, wasp larva, termites, ants, roaches, grubs, bugs, spiders, all insects. They are not vegetarians. You can buy moles on Ebay or trap some in your geographical location. A 1 quart glass mason jar in the bottom of a mole tunnel will catch moles.

Farmerboy
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The first year that I grew my garden, I was plagued with Cut Worms, Grubs and Root Wire Worms. The old man next door said to cover the soil with Wood Ashes and till it in. I spread the ashes from my wood stove and tilled them into the soil. I haven't had a Grub, Cut Worm, or Root Wire Worm since. Every 4 or 5 years, I treat my garden with ashes to keep the pest away.

The Wood Ashes provide Potassium, a necessary nutrient for plant growth. Wood Ashes are used by most commercial fertilizer manufacturers to provide Potassium.

Farmerboy
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Material on the bottom of the bed will not prevent cut worms or grubs.

Cut worms and grubs are the intermediate stage in the life cycle of a Moth. The moth lays the eggs in the soil in the fall. The eggs hatch around May and the cut worm emerges and feeds on your plants. In late summer, the worms pupate into moths, and fly off to lay eggs in someones garden and start the life cycle over.

Wood Ashes mixed in the soil will prevent cut worms and grubs. The worms do not like ashes. The moth will not lay eggs in soil with wood ashes mixed in it.

Most commercial fertilizers use wood ashes for Potassium. The ashes will make your plants grow better, unless you apply too much, then they will burn up the plants like any fertilizer.



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