Pumpkins with leaf problems

Discussion in 'Planting, growing, nurturing Plants' started by bonsai, Mar 10, 2010.

  1. bonsai

    bonsai Junior Member

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    Hey guys,

    I am currently having some issues with my pumpkins, it is the first time I have grown them on such a scale, I have about 15-20 plants in a 4m2 area..

    They seem to be getting what looks like mould on the top of the larger leaves, it is quite patchy and pale grey and seem to be spreading to the leaves directly beside those already affected and outward.

    I am thinking it is powdery mildew but have never encountered this in my garden before...

    We've recently had heavy torrential rain and some large hailstones that may have caused some damage, leading to an infection... but I am unsure what it is, and what I should do in this circumstance.

    I refuse to use any chemical pesticides or herbicides on my garden, so I am curious as to whether anyone has some suggestions or solutions?

    Thanks!
     
  2. purplepear

    purplepear Junior Member

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    I use some biodynamic preparations to combat this Bonsai. BD 508 is made from equisetium Avance and generally boosts the silica in the leaf to deter the fungus. It is sprayed immediately after rain which gets to be a bit painful if you get weeks of intermittent rain.

    The thing you can try that works well is to spray alternately with cider vinegar and bicarb soda, The trick is to change the pH on the surface of the leaf quickly from acid to alkaline. The fungus will not like this very much. I have used this on my grapes to good effect.
     
  3. hardworkinghippy

    hardworkinghippy Junior Member

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    Hi Bonsai,

    Some of the pumpkin family do have grey splotches on the leaves and are perfectly healthy. Here are some photos to give you an idea of what I mean.

    [​IMG]

    [​IMG]

    If they look like this, then you're OK.
     
  4. sweetpea

    sweetpea Junior Member

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    Hi, HWH. Yeah, it's powdery mildew. I get it all the time living in the fog. You won't be able to save the already affected leaves, but if you spray with a 2 tsp. baking soda solution and a few drops of a light cooking oil in a kitchen-sized hand sprayer, twice a week and right after a rain, the new leaves will be okay. It helps to have the plants in the sun most of the day. Shade encourages it. There are some types that are a bit more resistant. :)

    If you compost those leaves, make sure it's really hot compost. If y our having a real problem with it, don't use that compost around plants that are vulnerable. Tomatoes are vulnerable to this as well.

    When the baking soda dries it looks like a little powder, but the leaves underneath it will not turn brown and die.
     
  5. bonsai

    bonsai Junior Member

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    The leaves to do not seem to be suffering from the mildew... it just does not look that pleasing on the otherwise deep green-ness.

    The plants still seems to be fruiting heavily, I will attempt the baking soda and vinegar/oil methods to see if it improves the situation.

    My Roma tomatoes were planted qute close to the pumpkins, but they seemed okay at the peak of production (2wks-1mo ago) but declined rapidly, I think this may have been due to seasonal changes and heavy sporadic rain moreso than mildew though.

    Thankyou for your excellent advice so far guys!
     
  6. bilnrobn

    bilnrobn Junior Member

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    Our pumpkins, (and zucchinis), always get mildew towards the end of the season. We have given up worrying about it as the pumpkins are invariably unaffected and develop satisfactorily.
     
  7. pumpkin

    pumpkin Junior Member

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    It sounds bizarre but the method I use is one I gleened from ABC's Gardening Australia is to spray pumpkin leaves with a mixture of one part milk to ten parts water. It seems to work and can be used on zucchinnis and other curcurbits.
     

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