The Wicked Good Rope Wash by Sterling makes old ropes look and feel like new! One of the most commonly asked questions is "How do I wash my rope?" Sterling solves the problem with its easy, simple to use, safe, biodegradable rope wash. Available in pre-packaged 1-oz. packets with easy to follow wash instructions. One packet will wash one rope.
Sterling's Guide on How to Wash a Rope
"It is okay to use the hot water setting on your clothes washer as it likely won’t damage the rope. During the manufacturing process, the rope is exposed to high temperature steam. Damage to nylon does not occur until it has been exposed to over 300˚ water for over 5 hours. Use a non-bleach detergent soap like the Sterling Rope Wash™ [...]. Do Not Use Bleach! Hot water alone will also generally wash a rope pretty well.
Use a front loading washer or your bath tub but, realize the rope could get stuck and break the machine or damage the rope. The bathtub is the safest way. When using a washing machine, daisy chain the rope and put it in a mesh stuff sack. Run two rinse cycles to thoroughly rinse all the soap out of the rope. When using the bath tub, rinse until the rope runs clean. [...]
To dry the rope, hang it loosely out of direct sunlight. Do not use a heat drier as the heat may damage the rope."
Link: How to Wash Your Rope