Unless the ghillie suit smell like heavy swet, I'd keep it the way it is.

Mine is always in by car trunk. I think it only have the smell of dirt and paint. I only washed it once, locally because of some shit that go on the pants. Other than that, it still have some natural, rotting foliage of last year game attached to it! :D

Reminds me, everytime I dig it out, I still find sticks and crap stuck in mine. Lol