You do not wash dreadlocks. Hair must be dirty to dread.

 If you do not wash your hair it will stink. Dreadlocked hair needs to be washed regularly just like un-dreaded hair. You can wash dreads just as you would wash a sponge, by working the soap in and then squeezing and rinsing repeatedly to get all the soap out. Clean hair will actually lock up faster than dirty or oily hair. Because nearly every soap and shampoo on the market contains residues it was thought that clean hair does not dread quickly, when in fact it is the residues (conditioners, moisterizers, builders and fragrance holders) in the soaps that prevent hair from locking up. This is why we reccommend washing you dreads only in residue free soaps and shampoos