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Common household remedies request

Friggin Japanese (rose) beetles -- though not many -- chewing up my raspberry leaves. What to do?

I tried rotenone and copper yesterday, and there they are today, feasting away. Annoying!

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koan's picture
Submitted by koan on

This site suggests among a number of other things, "Bug Juice Spray", which for once is exactly what it sounds like:

Bug Juice spray: If you can handle it this is supposed to work. Harvest about 1 cup of beetles, put them in an old blender and liquefy them. Thin this with enough water to make it pass through a sprayer. Spray it on any plants they victimize. NOTE: If you make this out of beetles infected with the [biocontrol agent] 'milky spore disease' you will actually infect more grubs with the disease. So...if you can handle it give it a try!

Nature.. red in tooth and claw..

chicago dyke's picture
Submitted by chicago dyke on

i protect my area from JB with milky spore, traps, and some other stuff that works to various degrees. none of it matters, when my neighbors don't do the same. if i lived in an isolated area in which i could completely control four acres all around me, i'd be free of them. but it's hard to convince my neighbors to use the same as i do, or even to care that JB are killng off our native species and destroying our environment. sigh. just bitching as a suburban gardener. i don't have them here, but my neighbor's JBs just love flying over here for a little snack. recently, i saw a native bird, puking up a JB. damn thing didn't even fly away from me, and i was a foot away from it. native birds lack the enzymes to eat and digest them; JBs just make them sick. i'm not sure what JBs natural predators are, but i wish i had some, assuming they wouldn't also disrupt the native species chain.

meh, don't mean to be so doomy. milky spore works, and insecticide or the recipe above do as well.

chicago dyke's picture
Submitted by chicago dyke on


sorry. spray bottles are my bane. seriously. does anyone else have this problem? i buy them, and every single time i try to use a "thick" but strained substance in them, be it to demold my seedlings indoors or spray insect repellent or what have you, the damn things lock up after less than half a bottle.

i'm so glad i recycle. i have to use old spray nozzles from household cleaning bottles etc., just to have enough working spray units for my regular needs. i swear to Chuy i don't know why it has to be this way. but my god, we really need a 'sham wow' type guy to invent and sell a totally bitchin spray nozzle device, that will last for more than two weeks' use, and allow for use of liquids that aren't 100% pure water or the molecular equiv.

/end rant/

al_schumann's picture
Submitted by al_schumann on

I use milky spore and I managed to talk my neighbors into it (by explaining that skunks are attracted by grubs), but it's sometimes hard to maintain properly, and it gets pricey. I supplement with a hot pepper wax. It is very effective. You have to watch out for leaf burn and it becomes effective against humans if you don't dilute it enough. Otherwise, it's a good friend.

Submitted by lambert on

1. Milky spore

2. Hot pepper wax. Is that like Brazilian wax?

Also, totally with CD on the friggin nozzles. You'd almost think that a lousy nozzle design is a "nudge" to keep me buying bottles I don't need.

chicago dyke's picture
Submitted by chicago dyke on

you just have to grow the peppers yourself. i grew a mess of peppers two years ago, specifically for pepper spray, and i'm not out of them yet. i put some in a blender with some other anti-predator stuff like eggs and vinegar and soap, and as a spray, it works great. of course, spray bottles are still an issue. :-)

nomnomnom1's picture
Submitted by nomnomnom1 on

is to pull them off by hand and stick them in a mason jar, then when it is full, dump the jarful in soapy water to kill them; jbs move slower in the morning when it is cooler. I have tried the blenderize-the-dead-beetle method and it did not work for me. I have also tried neem oil spray which did not work for me.
Natural insecticides with pyrethrins kill jbs (eg Eco PCO WP-X) but they also kill lady beetles.
One can plant repellent crops near the raspberries and attractant crops away from them: r= catnip, thyme, chrysanthemum, chives, garlic, rue, tansy; a= blackberry, echinacea, evening primrose, borage, roses (esp. white ones), hibiscus, peony, soybean, zinnia (esp white ones): this will work some but is not enough on its own; one does run the risk of attracting some that would otherwise have been in one’s neighbors’ yards.
Mirabilis, larkspur, red buckeye, dwarf buckeye, geranium, and castor bean attract jbs but are toxic to them; however, they can be toxic to pets or children if eaten by them as well.
In addition to the milky spore (Bacillus popilliae) that can kill the grubs in the soil, there are Heterorhabditis bacteriophora nematodes available; I’ve never had enough of a problem to try these; they are not cheap.

Submitted by lambert on

I will get pots of geraniums and see if they attract and kill the beetles. Beautiful and useful!

chicago dyke's picture
Submitted by chicago dyke on

i have almost all of what you just listed r/a, and i find the pattern of JB attack on those plants very different here.

and i'll say that any "wash" of any kind, chemical, natural, homemade, concentrated... all it takes is one good rain and you're back to ground zero. i've learned that over and over, as every season i irrationally place my faith that this spray/wash/mix "will be different" and will last a long time. they don't. vigilance is your only real protection.

nomnomnom1's picture
Submitted by nomnomnom1 on

so maybe what the jbs like in Chicago would be more applicable? down here they love Rosaceae in general, esp tree fruits & raspberries. Hibiscus is possibly the worst hit plant, especially the H. moscheutos, but not the other Malvaceae I have so it's not something in the whole family apparently; my willows were hit in the drought when we were under water restrictions but not the last year or so; the jbs also love the echinacea but I have only one (white) variety.
They also seem to like any plant that is stressed: newly planted out shrubs (my Parrotia persica in its first year but not after), or like when I planted a zone 4 birch, lol, when it is 7b here.
I just pull them off: as you say, the sprays don't last and then i forget to spray again. I have never tried the pepper spray: I have too many cats; it's interesting to learn that it works well.

chicago dyke's picture
Submitted by chicago dyke on

and i've got a zillion of them. "dark lord" is my most common, but i also have pinks and white. no, JBs don't eat them but yes, they eat plants not three inches away from them. good luck in your area.

chicago dyke's picture
Submitted by chicago dyke on

given my schedule and the size of my beds. and i live in central MI now, despite my nym. :-) but yeah, they prefer some plants over others up here, and i'm never sure why. it seems to vary from year to year. last year, they totally killed a mess of my morning glories and my aronia bush. this year? the rosa sharons and buttercups took the hit. they aren't thick so far, but they are making an impact. lucky for me, not on the veggies, which is really all i care about.

my perennials have to be Fighters here. i don't have time to baby them. if they can't take one or two seasons of beetles, oh well. i'll move on.

Submitted by Elliott Lake on

a beneficial nematode that kills, very efficiently, similar beetles here. You apply it as a soil drench around the target plants, and it will easily kill off something like 80% in one application. I think you need to repeat for a few seasons, then sporadically. That bicontrol site may have it-- you may need to google for the correct nematode for the jb but I am sure there is one. I grow antiques and infuse the damask roses for my soaping, and make jelly and liqueur (don't sell that last one, alas! but I do the others)--the benefical nematodes I can't say enough good about.

Also, remove the hips and clean up around the base of the plants. Some of my roses are nearing 10' tall, so getting all the hips is impossible, but I prune them down some every few years for renewal, and that keeps me on top of the sitch so I can hand pick in between.

Submitted by Dromaius on

I love Japanese Beetles. They are beautiful. But I see your point.

To everything else, I wanted to add: Hand picking the ones that get past your other methods is a really good idea, because those are the STRONGEST ones. A lot of times, the control agents select for the strongest specimens and you definitely don't want those to reproduce.

Submitted by lambert on

... but it's another thing to have insects mating in your food. That's why I don't like them in my raspberries, leaving aside the damage they do to the leaves. I suppose it's not entirely rational, this feeling...