Prepare a dye bath as instructed in our Dip-Dyed Cups and Bowls, and, wearing rubber gloves or using tongs, fully submerge the mats in the liquid. Swish the mats around to ensure that the dye hits all the nooks and crannies; as with the paper vessels, experiment with longer dyeing times for deeper colors.
Place them on a paper-towel-lined tray overnight to dry.
Four quarts hot water
Bamboo place mats -- which can be purchased online and at import shops for less than $2 each -- look luxe when dip-dyed.