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Lepanthes Leaf Tip Dieback

Discussion in 'Issues, Disease and Pests' started by Chris.c147, May 5, 2022.

  1. Chris.c147

    Chris.c147 Well-Known Member

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    Does anyone know why the tips of my Lepanthes dieback? This happens on old leaves, as well as, new leaves. Doesn’t occur on any of my other genera.

    Temps between 64-80 and humidity stay between 80-95%. Constant air movement.

    0966271B-2E2A-430F-8FF6-178AA753F670.jpeg 81F1EE56-F346-4660-9A15-CEF6D335970D.jpeg BB3D75F7-D542-408C-B4F1-9B79FB53CE49.jpeg 20C6680F-8D82-47D9-BE17-260ABBE68351.jpeg
     
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  2. Marni

    Marni Well-Known Member Staff Member Supporting Member

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    Does it happen an all Lepanthes or just some? Are they all low elevation species? Generally, I think of leaf tip die back on Pleurothallidinae as coming from a concentration of fertilizer as the roots dry. The osmotic pressure pulls water out of the plant and it comes out first from the leaf tips.
     
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  3. EvanT

    EvanT New Member

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    Any possibility of a fungal infection? Some of my thin-leaved Lepanthes like lucifer and dactylopetala get black spots which spread in a similar looking way to your photos. Although the fact that it’s starting at the tips suggests maybe it’s something else. In my case I’ve always been able to stop the spots from spreading with a few sprays of an antifungal called Ortiva.
     
  4. Chris.c147

    Chris.c147 Well-Known Member

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    Marni, it’s only on my Lepanthes rhodophylla which is the only Lepanthes species I grow.

     
  5. Chris.c147

    Chris.c147 Well-Known Member

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    Evan, I’ve now sprayed my plant with Physan to see if that helps at all. I’m also going to stop fertilizing to see if that hinders the dieback.

     
  6. Marni

    Marni Well-Known Member Staff Member Supporting Member

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    The only person I know who grows this species grows this in the mid-50's at night and it does very well. Rather than stopping fertilizer, you could fertilize normally and then go back an hour later and water the plant. I've never found Physan to do much good.

     
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  7. EvanT

    EvanT New Member

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    For what it’s worth, the spray I mentioned is based on azoxystrobin.
     
  8. Ray

    Ray Orchid Iconoclast Supporting Member

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    You’re not alone Marni, but that’s because Physan is a topical disinfectant and infections are mostly systemic.

    If a grower is experiencing infections, it is often a cultural issue that weakens the plant to the point of susceptibility. If the environment is rife with pathogens (they all are, to one degree or another), spraying Physan on the floor, walls, benches, etc., can be an excellent way to knock their population down, albeit only temporarily.
     
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  9. Raven

    Raven Well-Known Member

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    I grow this species with 70F days and 60F nights and haven't noticed any problems.
     
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