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redshirtcat

Diagnoses? A few problems here..

redshirtcat
12 years ago

Hello - I bought quite a few miniature roses from John's Miniature Roses awhile back. They are doing reasonably well in little pots. However in the past 2 weeks or so I've begun to see problems. I spray once a week with Neem Oil and am very careful to spray the top and bottom of the entire plant. My in-ground hybrid Ts had a botrytis problem this season with all of the moisture so I've been spraying them with a copper fungicide once a week if the temps are above 60. If I spray the hybrids I spray the miniatures as well.

Here is what I'm seeing:

It looks like this Rainbow's End has aphids on the bud there - but what is the white stuff below with the little white looking bug in the middle of it? Will Neem control these aphids or should I try something else? High pressure water sprays are what I've been trying but I have to be careful since the plants are pretty tiny.

A lot of my roses (including the hybrid Ts) are doing this odd chlorotic thing with no evidence of blackspot or botrytis on the leaves. Some of the plants DO have blackspot but I see a lot of yellowing in places where there is no obvious disease. Any idea what might be going on? It usually looks like this:

I'm not sure what is going on here. If this is sooty mold or the beginnings of black spot or maybe even botrytis. I'm not sure how it could be fungal since this plant was 100% green 2 days ago when I sprayed everything with Neem and a day later with copper.

A *lot* of my roses have these small areas of nearly translucent leaves. No obvious disease anywhere on some of the plants but just these little paper-thin spots in the leaves. I assume this is some kind of insect but I don't know what kind? Will the Neem not kill whatever this is? What would?

Another shot from a 'Hot Tamale' plant:

This pic is large because I don't know if you can see what I'm talking about but I've also seen lots of this very thin webbing stuff around the buds and I don't know if this is natural or mite-related? If you can't see it click through and download the original, it's easier to see when it is large:

Thanks a lot for reading and any advice. I can spray as often as is necessary and have been picking off any diseased leaves.. I really want these to look nice.

Comments (5)

  • michaelg
    12 years ago
    last modified: 9 years ago

    I don't see anything here to worry much about.

    1. The aphids and spittle-bug won't do serious harm, just wipe them off.

    2., 3. Some scattered leaflets and leaves will just die for no evident reason. Ignore.

    4., 5. The translucent windows are from rose slugs, small green worms feeding on the underside. Just wipe them off. Predators will often control them for you. Oil or soap sprays should work if you coat the worms, but wiping off is actually easier unless there is a huge infestation.

    6. This may or may not be spider mites. Look with a 6x hand lens. Mites are normally found mainly on the undersides of lower leaves. I've only seen them on upper stems in the case of neglected plants grown indoors, especially in low wintertime humidity. It's possible this mini plant was infested when you bought it. Washing repeatedly with a strong spray of water will control mites effectively. Outdoor rains, humidity, and natural enemies usually keep them in balance. Use of chemical insecticides is the usual cause of flare-ups.

    Good luck. Sounds like you are a good, attentive gardener. The main things to keep up with are blackspot control and water.

  • redshirtcat
    Original Author
    12 years ago
    last modified: 9 years ago

    Thanks for the help Michael. I had no idea rose slugs existed. I checked the plants thoroughly and don't see any little green slug or caterpillar-like things.

    It's possible they were killed in the last spray but I will keep checking. In the process of looking for the rose slugs I *did* find some creatures on the underside of leaves and tried to get some closeups. These appear to be hanging by small threads from the leaves:

    Here's a wider angle shot:

    Are those maybe what the adults look like? I googled and the adults look more like actual flies to me.

    I also found this other critter and got a closeup of him as well. It doesn't really look like an aphid and I don't know if he's causing any damage or not?

    This one looks like a mosquito to me but I don't know my bugs all that well. Maybe it's a mature sawfly? This is the best pic I could get and it doesn't look much like them to me...

    Anyway - I appreciate the help and will keep on top of the blackspot and watering for sure. My poor Hot Tamale just looks like it's being eaten into oblivion by the yet-to-be-found rose slugs...

    Thanks!

  • york_rose
    12 years ago
    last modified: 9 years ago

    The first two pictures are good guys. Those are lacewing nymphs hatching from their eggs. They're ferocious predators of pests like aphids.

    Third picture is an adult female aphid, possibly one named Macrosiphum euphorbiae. The bloated and yellowish appearance of it might mean it's dying as a result of being eaten alive from the inside by an another sort of insect predator known as a "parasitoid". (Or it might not mean that. Was it walking around at all?)

    I think the final picture is either a dead aphid or a molted aphid skin.

    Look on the undersides of the leaves for small pale green "worms". That's where rose slugs hang out.

  • york_rose
    12 years ago
    last modified: 9 years ago

    One caution on using copper spray as your go-to fungicide with roses.

    Some roses can't tolerate it. One year before I knew this I sprayed a White Rose of York (Rosa alba semi-plena) with copper spray to control blackspot.

    During the following two weeks the bush dropped all its leaves.

    Make sure your roses tolerate copper fungicide before using it all over the bush. :)

  • redshirtcat
    Original Author
    12 years ago
    last modified: 9 years ago

    Thanks so much. I don't really know anything about insects of any kind. I'm trying to learn rapidly now that I see them all over. I thought for sure that those hanging eggs were trouble and I'm glad to know they are what lacewings look like (I ordered lacewing eggs on cards a few weeks ago, maybe this is the 2nd generation!).

    Thanks again!

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