Washing Soda or Borax is also a wonderful additive (both can be found in the laundry section of the store). It helps break up and prevent that soap buildup, which is usually caused by hard water. The minerals in the water bond to the soap, and create a grey dingy gunk, and reduces the effectiveness of the soap, and also creates too much water tension so the water cannot get into the fibres to remove the dirt. Once the minerals in the hard water are broken down, the organic matter that's imbedded in the fibres of the clothes or ratty blankets can get out. With hard water and sticky soap buildup, the organic matter gets trapped, and that's why there's still a "smell" even after you wash.
Don't use fabric softener. It also coats the fabric with a greasy film, which is difficult to wash out.
A cup of white vinegar in the rinse cycle will help with softness, and is generally less expensive than liquid softener.
