catwhiskas, have you tried contacting the Recreation and Parks Department in Denver? They might know of a source for mulch and be able to lead you in the right direction. That's who we would call around here; it's worth a shot.

Hi Claire, that was my going to be my second phone call.

I just found out thru Rocky Mountain gardening forum that any local tree service company should be glad to provide you with mulch for free as it saves them a trip to the landfill along with saving them landfill fees.

I already have them dropping some mulch off tomorrow.
Thanks!