Dreadlocks normally stay clean for quite awhile, but it's not uncommon for wax, styling products and other debris to build up in your hair. Your usual shampooing won't be enough to get rid of excessive built-up residue. Soaking your hair in dreadlock soap, though, usually does the trick. If you'd rather use a home remedy, try baking soda and vinegar. The fizzing action dissolves residue, leaving your locks soft and clean.
Fill a large bowl or sink with 1 gallon of water. Add 2 tablespoons of liquid dreadlock soap or shampoo, then mix well until suds form.
Soak a towel in the soapy water. Wring out the excess moisture, then wrap the towel around your hair.
Allow the soapy water to soak into your hair for 10 minutes. Remove the towel.
Rub dreadlock soap into each individual lock. Work your way down from the top of each lock to the tip. Let the soap soak in for five minutes.
Rinse the soap out under very warm or hot running water. Keep rinsing until no more suds remain.
Baking Soda and Vinegar Method
Wet your dreadlocks thoroughly, then towel dry so your hair feels damp.
Fill the palm of your hand with baking soda. Sprinkle the baking soda liberally over your scalp and all surfaces of the dreadlocks. Rub it into each lock.
Fill a spray bottle about halfway with apple-cider vinegar. Spray your hair with the vinegar. As it reacts with the baking soda, the mixture will start fizzing. This means that the mixture is breaking down buildup and cleaning your locks.
Rinse out the vinegar and baking soda under running water. Shampoo as usual.