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Mold!

Discussion in 'Issues, Disease and Pests' started by staceyb86, Dec 13, 2016.

  1. staceyb86

    staceyb86 New Member

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    Hello, I'm completely new to the forum and a newbie orchid owner. Despite watering to what I thought was correct I have mould :(
    I have removed effected roots and have a new pot and bark for it.
    I have read about using original listerine to wash the roots as antifungal before repotting. But I just can't get my hands on any. Are there any other things found on the home that can be used? Or should I just rinse off the roots and repot and keep my fingers crossed?
    Many thanks
    Stacey
     
  2. staceyb86

    staceyb86 New Member

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    [​IMG]

    As you can see it is looking a little sad at the top too and I'm a bit unsure where to trim it :-/
     
  3. Kipper

    Kipper CoffeeCoffeeCoffee... Supporting Member

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    Hi Stacey, And welcome to the forum. The second pic looks like you are growing a new spike. I would cut it off half way between where it branches and the wire holding it to the stake. As far as an anti fungal goes I use Physan but there will be someone on the forum that can tell you more than I can about more common household products you could use. Phals. are much more resilient plants than you would think though. Good luck with it.
     
    staceyb86 likes this.
  4. jai

    jai Orchid addict

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    Listerine the gold brand
     
  5. DPfarr

    DPfarr Well-Known Member

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    Hydrogen peroxide works too.
     
  6. Ray

    Ray Orchid Iconoclast Supporting Member

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    Mold won't grow on healthy, living tissue. If mold is growing on the potting medium, change it. If you find necrotic tissue on the roots, trim it off, and dab the cut ends (and no more) in cinnamon powder, which will seal the wound and protect from further infection.
     
  7. staceyb86

    staceyb86 New Member

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    This is what I did in the end. Thank you everyone :) hoping it will be happier now! Might treat myself to another orchid over Christmas with some left over garden centre vouchers I have!
     
  8. nora von gerichten

    nora von gerichten New Member

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    Original Listerine will kill delicate roots. It is okay, I guess for mature orchids with thick roots.

    Be careful about cinnamon. What we get in the stores is not true cinnamon, which is very expensive and only sold at specialty shops.

    Physan cannot be sold in Canada.

    H2O2 works excellently, but only if there is lots of air circulation. Add more fans.
     
  9. Latouria Lover

    Latouria Lover New Member

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    The cinnamon we get in stores and the type that comes from Ceylon which is considered to be true cinnamon all come from trees of the Cinnamomum genus and all contain cinnamaldehyde which is the active ingredient that has anti-fungal properties.
     
  10. Seattle Steve

    Seattle Steve Member

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    Hydrogen peroxide according to one person who wrote their Masters paper on it, is better than cinnamon. Not the cinnamon won't work, just that it isn't as effective according to his thesis. Hydrogen peroxide is produced naturally in plants and will help initiate root growth. I'm not the expert on this, but the grower is and I find it easy to use. Just be sure it is fresh and stored in a dark cool place. It breaks down easily and has a short shelf life. I am amused what people do with all sorts of products intended for dental use, such as Listerine. I am sure it simply the alcohol in it that is the active ingredient. Not really good for your oral tissues either. Get some of that Kelp extract from Ray - that will kick that plant into gear! Works great for me.
     
  11. Ray

    Ray Orchid Iconoclast Supporting Member

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    The problem I have with the standard drugstore grade of hydrogen peroxide (stabilized for storage using stannous chloride) is that it decomposes almost instantly upon contact, leaving a pool of water in which fungi can grow. However, if you can get some Biosafe Disease Control, it is a more dilute hydrogen peroxide that is stabilized with perchloroacetic acid, so it stays chemically active until it is dry.

    I have used the stuff for several years, and seen absolutely no phytotoxicity. Back when I was shipping a lot of plants, I would moisten the medium with it, knowing that it would prevent the growth of pathogens while providing a little bit of water.
     
  12. Latouria Lover

    Latouria Lover New Member

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    Hydrogen peroxide is more stable in an acidic environment. The molecule is not stabilized by acid. There is a difference between the two things. It is also very stable when in very low concentrations. Hydrogen peroxide releases an oxygen when it comes into contact with a catalyst. That can be the correct biological enzyme produced by tissue or pathogens, or metal, or sunlight, or slowly in an alkaline, or very slowly in a neutral environment. All molecules of hydrogen peroxide will be active until it reacts which is an indication of activity (that is how it works) or until it is all used up because there is a lot of catalyst around or until it dries.
     
    Last edited: Dec 15, 2016
  13. Ray

    Ray Orchid Iconoclast Supporting Member

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    However it works, the less-concentrated H2O2 in the Biosafe product is far more effective than drugstore stuff.
     
  14. Ray

    Ray Orchid Iconoclast Supporting Member

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    However it works, the less-concentrated H2O2 in the Biosafe product is far more effective than drugstore stuff.
     
  15. Ray

    Ray Orchid Iconoclast Supporting Member

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    However it works, the less-concentrated H2O2 in the Biosafe product is far more effective than drugstore stuff.
     
  16. naoki

    naoki Well-Known Member

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    I agree with what Ray said in message #6. But with regard to H2O2, is there a scientific evidence that it kills fungi? Biosafe product seems to work against some fungi.

    I looked a little into it, but didn't spend enough time.
    The bactericidal, fungicidal and sporicidal properties of hydrogen peroxide and peracetic acid
    This paper shows that it can be bacteriostatic at 3% (meaning stops the growth of bacteria), but it doesn't kill them.

    There is a paper about fish egg fungi vs H2O2, but I didn't read it. I'm guessing that fungi is more resistant to H2O2 than bacteria.

    It is also interesting that the exact mechanism of how H2O2 kills microbes is not completely known:
    Use of hydrogen peroxide as a biocide: new consideration of its mechanisms of biocidal action
     
  17. DPfarr

    DPfarr Well-Known Member

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    Peroxy bonds are funny. I've always wondered about that mechanism too. Does it get deprotonated and then react? Does the peroxy bond break and it reacts as a base? I also assumed the latter happening when sitting in a car ride or other tedious things when the mind it allowed to roam.

    Also, I used it on a Lepanthes once and felt certain a reaction with the H2O2 was why it died. Where having (assumedly) a reduced cuticle would lead to greater susceptiblity to tissue damage. Other things I remember devoting minimal thought and time to.
     
  18. Marni

    Marni Well-Known Member Staff Member Supporting Member

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    I've used 3% H2O2 (from the drugstore) to clean the leaves of lepanthes of algae. I wash it off with water once I've finished and have never had any damage.
     
  19. Korina

    Korina Member

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    On a slightly different note, staceyb86 you might want to take a critical look at your conditions; mold is usually a symptom of too much moisture and/or not enough air circulation.
     
  20. staceyb86

    staceyb86 New Member

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    I've now taken it out of the dark ceramic pot that it was in and it is now sat on a saucer. I had been placing the pot in water for 5 mins every 7 days but obviously over the cooler months this has been too often. It had been blooming and looking great until just a week or so ago. Hopefully it will perk up now :)
     
    Korina likes this.