The same characteristics that make merino wool such a luscious and soft material also make it delicate when it comes to washing it. It's important to handle your merino wool with care. Don't hang it from a hanger (it will stretch), don't stick it in the washing machine or dryer, and be warned that heat is wool's enemy. Grab yourself a bottle of Woolite from the grocery store to keep around the house for hand-washing your merino wool blanket when it's time to give it a bath :)
You can find some excellent advice on caring for merino wool at the following two links listed below. Both links are talking about sweaters, but the same advice applies to blankets. Also, just a note that the merino wool I use is HAND WASH ONLY, disregard the section in the Woolmark link which discusses treated wool that can be machine washed.
The Woolmark link is a very informative pdf file which describes everything from washing to storing to stain removal, including for specific stain types. I recommend you download it to keep on hand for future use in case you need it.
Here are the links to click on:
Martha Stewart article on hand washing merino wool sweaters
