Join Date: Feb 2015
Location: Southern California
If the base is not too heavy, I would take it outside and shake the heck out of it. That's what I used to do with all of my own artificial trees years ago (now I don't keep these dust collectors around!) :-)
Since it hasn't been dusted in so long, I would also take my Swiffer duster or cobweb brush and kind of get all up in there and break up some of the cobwebs, and then shake it some more. Some of the leaves will fall off, but just discuss with the client to ask if this will be all right.
I would only dust, not clean, this. Takes too much time and the results are unsatisfactory, at best, with the silk plant cleaners that you spray and leave.