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3 messages
23/09/2013 at 13:21

I have a number of white cosmos, up to about 4ft tall and flowering. But then they all started keeling over - looked like something had eaten through the main stem. Also noticed that there were groups of wasps on the fallen plants, looked like they were eating it.

I didn't know wasps did this, and is there any way to prevent it in future ?

23/09/2013 at 19:55

Hello blueberry77, 

Firstly, the wasps haven't got it in for your cosmos. Something else, such as slugs and snails, will have had a go at them. Wasps like to eat sweet things, suchas nectar, and meaty things, such as other insects. 

I don't know for sure, but I would think that the fallen plants are exuding some sort of sugary liquid and the wasps are drinking it.

24/09/2013 at 19:19

The stems were partly cut through about 3 inches up, didn't look like what you'd expect from slug damage. The sap must be sweet, there were groups of wasps feeding on it.

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