Although washing wool takes extra time, care and attention to ensure you don’t ruin the material, it can also now easily be done in the washing machine thanks to innovations in technology and specially designed cycles.
Check Your Manufacturers Care Label 
The first thing you should do before washing any piece of wool clothing is to check the manufacturer’s care label. This typically provides special care instructions for washing, removing stains, and generally caring for the piece of clothing to ensure it keeps its quality.
Use Your Wool or DelicateCycle Setting 
Whatever washing machine you have, there is sure to be a cycle setting that is best suited for your wool garments and sweaters. If you don’t have a delicate cycle or a specific ‘wool’ option, then you will probably have a hand wash feature that you can alternatively use. Some pieces of wool clothing, such as certain types of coats or trousers, should only be dry cleaned, and some items should also be hand cleaned rather than put in the machine. Their care labels should specify which option is best.
Things to Consider When Washing Wool in a Washing Machine 
  1. As wool is a self-regulating and delicate natural fiber, it doesn’t require regular washing and should be cleaned less frequently.
  2. Spot clean any stains when possible and be sure to gently blot rather than rub.
  3. Separate your darks and lights when washing as removing color from natural fiber fabrics such as wool can be difficult.
  4. Soak your wool clothing in cold water before washing to prevent shrinking.
  5. Use a cold-cycle wash as even water that is slightly warm will cause wool to shrink.
  6. Always air dry wool clothing after washing them – don’t tumble dry them.
  7. Use a gentle detergent, and turn the garment inside out before washing to prevent damaging the material.