I give my truck a rinse once every 2 weeks or so, and give it a real soap wash once a month. I haven't gotten around to waxing it since it was purchased back in early November.
Pollen is on an assault here so I had to rinse it this past weekend. No point in washing yet, because 2 hours later and there is already pollen accumulating again. Good thing all that rain came through and hopefully hosed out majority of the trees/plants