GOLDEN VALLEY, Minn. - There are many ways to prevent and reduce Japanese Beetles. We want to thank Bachman's for letting us pop by and look at many of the products. Here is there info sheet on dealing with them.
Here are Bobby's tips
Tip 1: Water Properly
The first step in Natural Grub Prevention is to water your lawn properly. How does watering affect
grubs? Japanese Beetles come out of the ground in late June, and feed on plants through the summer, and then lays eggs that turn into grubs in the fall. Have you ever watched Japanese Beetles closely in the summer and how they are mating right around now, getting ready to lay their eggs.
In order for the Japanese Beetle Eggs to turn into grubs, they need moisture. So, if you water your lawn
every day during the summer, you're giving the grub eggs just what they need to survive! So if you don't
water your lawn, it will probably go dormant but it will be less likely to have grub damage.
Tip 2: Plant Deep Rooted Grasses
The best way we've found to prevent grubs organically without using any chemicals or products at all is to plant Turf Type Tall Fescue (Midwest) that has a really deep root system and can get by with one deep watering every 7 days even in periods of hot dry weather. Shallow-rooted grasses like creeping bentgrass show a lot of damage from grubs because there just aren't a lot of roots to spare.
Tip 3: Use Beneficial Nematods to Kill Grubs - Naturally!
What if you don't have a Tall Fescue Lawn and you're concerned that you might have some grub problems? The best time to kill grubs in a lawn without chemicals is in the late summer or early fall
when the new grubs are really small. We've found that Beneficial Nematodes will eliminate 50-75% of
the grubs in your lawn and that is usually enough to minimize the damage. What? You want to kill all
the grubs? Well, that just isn't necessary or even possible. A healthy lawn can withstand up to 6 grubs
per square foot. If you have an average American lawn (8,000 square feet or 1/5th of an acre) your lawn can withstand 48,000 grubs before showing signs of damage.
Beneficial Nematodes are Microscopic Worms that occur naturally in all soils. Like people, there are
good nematodes and bad nematodes. The bad nematodes it plant roots, and the good nematodes
attach themselves to grub larvae in the soil and suck the life out of them. Most soils are lacking in good
nematodes so it helps to apply a few extra early each fall to reduce the number of grubs in your lawn.
How to Apply Beneficial Nematodes for Natural Grub Control
Beneficial Nematodes for Grub Control are easy to apply. A hose end sprayer is probably the preferred
method of application. The nematodes come in a powder and you add the powder to some water in
your hose end sprayer, shake it up, and apply it over the area you'd like to treat until you've used up the
right amount of nematodes. Nematodes can die in the sunlight so it helps to use a lot of water when
you're applying them and water them into the soil. If you make the application in the evening that gives
the nematodes all night to work their way into the soil before the sun comes up the next day.
The University of Minnesota does not recommend Milky Spore for Natural Grub Control.
Good horticultural practices, including watering and fertilizing, will reduce the damage caused by these
beetles, but oftentimes you simply need to get rid of them. Here are some ideas:
Row Covers: Protect your plants from Japanese beetles with row covers during the 6- to 8-week feeding period.
Hand Pick: Unfortunately, the most effective way of getting rid of Japanese beetles is to hand pick them. It’s time-consuming, but it works, especially if you are diligent. When you pick them off, put them in a solution of 1 tablespoon of liquid dishwashing detergent and water, which will cause them to drown.
Neem Oil: Neem oil and sprays containing potassium bicarbonate are somewhat effective, especially on roses. The adults ingest a chemical in the neem oil and pass it on in their eggs, and the resulting larvae die before they become adults. Neem can be harmful to fish and should be reapplied after rainstorms. Use a Dropcloth: Put down a drop cloth and, in the early morning when they’re most active, shake them off and dump them into a bucket of soapy water.
Insecticides: If you wish to spray or dust with insecticides, speak to your local cooperative extension or
garden center about approved insecticides in your area.
Or, try this safe homemade solution: Mix 1 teaspoon of liquid dishwashing detergent with 1 cup of
vegetable oil and shake well; then add it to 1 quart of water. Add 1 cup of rubbing alcohol and shake
vigorously to emulsify. Pour this mixture into a spray bottle and use it at ten-day intervals on pests.
Homemade sprays can run more of a risk of damaging plant leaves, so be careful. Apply sprays in the morning, never in full sun or at temperatures above 90ºF. If your plants start to wilt, rinse the leaves immediately with clean water.
Traps: Japanese beetle traps can be helpful in controlling large numbers of beetles, but they also might
attract beetles from beyond your yard. Eugenol and geraniol, aromatic chemicals extracted from plants,
are attractive to adult Japanese beetles as well as to other insects. Unfortunately, the traps do not
effectively suppress adults and might even result in a higher localized population. If you want to try
them, be sure to place traps far away from plants so that the beetles do not land on your favored plants
on their way to the traps.
Fruit Cocktail: You can buy Japanese beetle traps of all sorts, but most are no more effective than a can of fruit cocktail. Open the can and let it sit in the sun for a week to ferment. Then place it on top of
bricks or wood blocks in a light-colored pail, and fill the pail with water to just below the top of the can.
Place the pail about 25 feet from the plants you want to protect. The beetles will head for the sweet
bait, fall into the water, and drown. If rain dilutes the bait, start over.
Geraniums: Japanese beetles are attracted to geraniums. They eat the blossoms, promptly get
dizzy, fall down, and permit you to dispose of them conveniently with a dustpan and brush. Plant geraniums close to more valuable plants which you wish to save from the ravages of Japanese beetles.
Japanese Beetles on Roses? Note that insecticides will not fully protect roses, which unfold too fast and are especially attractive to beetles. When beetles are most abundant on roses, nip the buds and spray the bushes to protect the leaves. When the beetles become scarce, let the bushes bloom again.
Timeliness and thoroughness of application are very important. Begin treatment as soon as beetles
appear, before damage is done.
HOW TO PREVENT JAPANESE BEETLES
Unfortunately, there is no magic potion to get rid of this pest. For general preventive maintenance,
experts recommend keeping your landscape healthy. Remove diseased and poorly nourished trees as
well as any prematurely ripening or diseased fruits, which can attract Japanese beetles.
Try these tips:
In the grub stage of late spring and fall (beetles have two life cycles per season), spray the lawn with 2
tablespoons of liquid dishwashing soap diluted in 1 gallon of water per 1,000 square feet. The grubs will
surface and the birds will love you. Spray once each week until no more grubs surface.
You can introduce the fungal disease milky spore into your lawn to control the Japanese beetle larvae
population. The larvae ingest the spores as they feed in the soil. The spore count must be up for two to
three years for this method to be effective. Fortunately, the spores remain viable in the soil for years.
This is an expensive treatment, as all the soil within five-eights of a mile needs to be treated for good
You can also drench sod with parasitic nematodes to control the larvae. The nematodes must be applied when the grubs are small and if the lawn is irrigated before and after application. Preparations
containing the Heterorhabditis species seem to be most effective. Companion planting can be a useful strategy in preventing pests. Try planting garlic, rue, or tansy near your affected plants to deter Japanese beetles.
You can also attract native species of parasitic wasps (Tiphia vernalis or T. popilliavora) and flies to your
garden, as they are predators of the beetles and can be beneficial insects. They will probably attack the
larvae, but they are not very effective in reducing the overall beetle population.
Many dusts or sprays are highly toxic to honeybees. If application of these materials to plants is
necessary during the bloom period, do not apply during hours when bees are visiting the flowers. If
larger than yard and garden plantings are to be treated, you may need to contact nearby beekeepers in
advance so that they can protect their colonies.