How can we remove drain fly from a plant display?

Posted by ian terry on October 16, 2003 at 05:08:12:

In Reply to: Drain Fly Larvae? posted by Zach on September 10, 2003 at 01:43:12:

At present I am responsible for the car of living foliage plant displays in an office building. The Pest |Control Officer has traced drain flies from the roof area and they are now to be found in the soil in the plants where presumably they are breeding. Can you please advise whether this is a common problem ? Your advice as to how I may be rid of these would be valued. Do you suggest that all of the pots are emptied of soil and that the plants are repooted into fresh compost ? Thank you.

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