This is from a MARTHA STEWART ARTICLE by Tina Chadha (Style Editor) and consistent with what we’ve been advising.
The Best Way to Wash Wool and Cashmere Sweaters
To help you understand why it's possible to wash wool and cashmere at home, you must first understanding the fabric. "All animals in the wool family, whether sheep, alpaca, mohair, lamb, merino, or camel use the same cleaning process," says Whiting. Her advice: It's always safer to hand wash. Fill a sink, tub, or basin with tepid water and add a squirt of a cleanser that's specially formulated for wool, like The Laundress Wool and Cashmere Shampoo. Don't have any on hand? "The alternative is a good hair shampoo, because wool and cashmere is hair," she says. Next, submerge your sweater in the bath. Gently swirl it around for about 30 seconds, and let it soak for up to 30 minutes. Drain the dirty water and rinse with cool, clean water. Next comes the most crucial step: "Avoid that gut reaction to wring it," stresses the expert. "Wringing manipulates the fibers, and when the yarns are wet, they're weaker. You might end up disfiguring your sweater." Instead, gently remove the water by pressing your sweater into a ball (think: pizza dough). You can even press the ball into the side of the sink or your work surface.
How to Wash Wool and Cashmere Sweaters in the Washing Machine
Though Whiting prefers hand-washing, she says that the washing machine isn't off limits. For best results, place your sweater in a mesh washing bag. Select the delicate cycle on the machine, and make sure the water temperature is cold and the spin is on low. "You can shrink or felt an item by overly agitating it," she warns. "That's having your machine on too high, or really going to town with the item while hand washing, is a problem." Once the cycle is complete, promptly remove the sweater to reduce creasing.
How to Dry a Sweater
Whether you wash your sweaters by hand or in the machine, our expert stresses that they should stay far away from the dryer, which is notorious for shrinking knits. Once you've gotten the excess water out, lay the sweater flat on a clean towel or drying rack and re-create its natural shape. Let it air dry. To speed up the drying, roll the sweater up in the towel like a sleeping bag. Then, unroll it and replace the wet towel with a fresh dry one or place the sweater on a drying rack and reshape it again. A major no-no: Hanging your sweater up to dry. "You're going to end up with a sleeve sagging in a place it shouldn't be," says Whiting.
How to Treat Stains
Is that ketchup on your sweater? Don't freak out and dab like crazy—that will just make it worse. Whiting recommends working a stain remover into the area before the next wash. But go easy with the application. "If you're scrubbing it with your fingers or a scrub brush, you're going to have a visual result," she says. "You're either going to disrupt the weave or cause it to be super fuzzy." Gently massaging it in will do the trick.