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Cobwebs on compost

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For many years I have used a heated propagator in the greenhouse to start my seeds off. This year some of the seed pots have had a fine white cobweb develop on the surface of the compost. I can rub this off with my thumb but it comes back almost overnight. I remove the lid from the propagator during the day once the seeds have germinated. Even seedlings I have pricked out into new compost have developed this cobweb surface. Not all the seed pots have been affected. Any ideas as to what is causing it and should I treat it?



I wonder if its from the compost? As you,ve used the propagator for some years you,d know if its too wet etc.

17 Mar, 2012


Are there any caterpillars anywhere you can see, at either end of the silky path/trail through your seedlings?

17 Mar, 2012


its not a fungi bye any chance as they like dark warm conditions and can look at a glance like spiders web ?

19 Mar, 2012


Noseypotter's suggestion 'rings a bell'!! Did you ever have mushrooms, or mushroom compost in your compost? If so, then it could well be a fungi of some sort and you will need to treat with appropriate fungicide.

21 Mar, 2012


Thanks for responses. The compost was a bag of multipurpose which was bought last year but was unopened until mid Feb this year. I have since stopped using it and purchased fresh as I also had problems with cabbage seedlings - were fine until I pricked them out into individual pots and returned them to the propagator where they slowly succumbed one by one to some sort of wilting disease. I don't think it was damping off as the stems were (and still are) strong and sturdy. The seed leaves withered, and looked a bit like powdery mildew. I sprayed with a solution of bicarb of soda and soap but it hasn't stopped the continuing demise of every plant leaf by leaf. I have now resowed all varieties - fingers crossed. I'll use the bag of compost on my ornamentals!

29 Mar, 2012


your more than welcome .

30 Mar, 2012

How do I say thanks?

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