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Please help-spider mites?

18 years ago

I have searched the forums and have tried a couple of sprays (Bayer rose spray) and Safer insectecidal soap, I even tried the Bayer 3 in 1 that you pour in the ground as the rose guy at the farmer's market suggested, but my roses are still covered in spider mites, or at least their webs!

I don't know what to do excpept cutting them down, please help. Do you have any advice or suggestions?

Just as a background, these are bareroot roses that I planted this spring. They were doing exceptionally well, until the aphids attacked. Well i got rid of those effectively with Safer, but now I have some that are just covered with spider mite webs. None of the treatments seem to work, and I feel like I might lose one of my Compte du Chambord roses. (Is that variety more suseptible?)

(In fact, I have two Compte du Chambord and one is dying from a spider mite infestation and the other one, which is not by 3 feet from it, is growing really tall, but it has no buds on this last growth. Is that normal? The one with the infestation has a flower!)

Also, I'm having fungus/mildew issues. The brown spot kind, but I don't water at night. The soaker hose goes off at night and in the morning, what else could be causing this?

Any help and advice will be greatly appriciated!

Comments (11)

  • 18 years ago

    Spider Mites likely won't kill your rose, but I hate 'em, too.

    Can you hose-wash them every other morning or so for a couple of weeks?
    I'm talking powerful hose spray, hopefully directed UP from under the plants.
    Failing all else, put a whirly sprinkler under the plants, and turn it on full-bore in the morning, while you dress.
    (This will also hold down the aphid population.)

    Avoid non-specific insecticides, as these really promote big spider mite colonies.

    It is difficult to diagnose your fungal problem without seeing it.
    If you don't have a digital camera, can you put some leaves in a flatbed scanner?
    This will give you some good clear images.
    (I learned this trick from Fa Shimbo, in CO.)

    Jeri

  • 18 years ago

    I hate spider mites! The only reason I ever use chemical pesticides is to treat spider mite infestations. I only get spider mites in the Spring when I buy new potted roses. The spider mites then happilly proceed to consume all my roses. None have ever died yet, but they have looked very bad for awhile.

    I think you should break out the chemicals and zap them. Hopefully you will only need to treat them a couple of times. I wouldn't generally encourage pesticide use, but they are devils that must be stopped!

  • 18 years ago

    No need to use chemical warfare for spider mites. I've had spider mites twice this year in my Knockout tree rose. Both times, the leaves were all pretty much goners before I noticed them. Both times, I just blasted the leaves every morning with my regular hose-end nozzle (from the underside as Jeri said as well as from the top). This knocked off any leaves that were ready to fall as well as knocking off the stupid little mites. The rose recovered, re-leafed, and is doing beautifully. I now spray it every few days just as preventative.

  • 18 years ago

    Thanks everyone for the tips.

    I've determined that the spots are blackspot, now to figure out how to get rid of it. I pick off the effected leaves, but there are so many! Do I have to get every single one?

    I'm still not sure what the other problem is, I think it might be effects of spidermites who are now gone, because I don't see anymore.

    I've scanned the photos, but can anyone tell me how I post them? I don't see a way....

    Thanks again,
    Larisa

  • 18 years ago

    Larisa, to post photos, you need to get a Photobucket account.
    Then copy and post the html line for the photo you have uploaded.
    (Yeah, it's a little arcane.)

    If you don't feel up to coping with it, email directly to me, and I will tell you
    how to send the photo to me. Then I will be happy to post it for you.

    Jeri

  • 18 years ago

    Two words.......neem oil. I use it on my brugmansia, it's a spider mite attractor. You need to reapply it in a week. It's natural, smells good(like citrus) and I get about an 8 month break before I do it again. One bottle of neem oil costs about $9(it's a concentrate). It really works!!!

  • 18 years ago

    Very bad for bees, however.

    Jeri

  • 18 years ago

    One thing to keep in mind when fighting spidermites. They are NOT INSECTS! So insecticides won't kill them. You need to use a miteacide,I think Ortho has a product with a mitecide in it.
    Blackspot try to find some Manzate, which is zinc and manganese. Spray your bushes with it every three days for at least two weeks. This chemical will kill the blackspot. Then you can use a good preventitive like Bayer Rose Disease Control Then you can say bye-bye to blackspot!

  • 18 years ago

    Hi. It is a drag, but the only thing that has ever really gotten rid of the mites is the blast of water every day, from under the leaves. I was told that the blast of water kills the mite by ripping their bodies from the sucking part (mouth) of the mite. Gruesome, but it works!!

    Once I stopped using insecticides, my mite problem went away because the chemicals were killing the bugs that ate the mites.

    This year I needed to use an insecticide again for midge and wouldn't you know it: the plant I was spraying, and the two neighboring plants, now have mites.

    My favorite spray for fungus is Bayer Advanced Disease Control; Concentrate in a blue 32 oz bottle, about $15. It kills existing BS and prevents BS. I live in hot, humid Maryland and nothing has worked as well as this and you only need to spray every 2-3 weeks. yay! I can only find it at some Lowes, so you night want to call first to make sure they have it.

    Don't despair! Start blasting those mites and get that Bayer! ; )

  • 18 years ago

    If you over-use insecticides, you get rid of any insect predators of spider mites that would normally keep the population down. I'm guessing this problem is the after-effect of your earlier battle against the aphids.

    Reflected heat from walls or concrete patios also encourages them to breed.

    Spider mites are not insects, but related to spiders, so acaricides can be used to kill them. However, I prefer to hose off the leaf undersides every other morning, which was previously recommended, as this has also worked best for me.

  • 18 years ago

    Spider mites can kill plants. If you doubt it, just come and look at all my neighbors and our tomato plants (this year and last). All are almost totally defoliated now by the little @#(&!!. Spraying plants with forceful jets of water every day for days/weeks may work for a minor infestation (and I've used it for that myself), but if they have arrived en masse and have attacked several plants you will need to do more then spritz them with water (where they can fall to the ground and climb right back up again). And unlike our cooler cousins up north, in our looong hot summer climate spider mites have time to reproduce like rabbits, hatching every 3 days until a freeze. They are a force of nature, and whether you spray insecticides or not (and I normally never do), spider mites arrive every year in my garden in spring. A Godsend to me was the introduction of AVID in the 80's. It's active ingredient, Abamectin is a naturally occuring soil microorganism, and as such it's effectivness is limited to only certain " bad bugs", such as mites. There are 5 things that you need to be aware of when using AVID. (1) It works, (2)It is translaminar, which means that it penetrates the leaf surface and is inside the leaf was well as on the outside, (3)You are to use it only when you have an infestation, never as a preventative. Mites will build up a tolerance to it if over used making it useless. That btw, is a guarantee. (If you get past #4 here, then you should ask about the spray schedule)(4)It is expensive but (5) It works.