You can use natural dyes to color eggs, some seashells, sea life (like sand dollars), cloth, and more. Nature provides us with an abundance of color. Natural dyes can come from herbs, flowers, vegetables, berries, and more.
Place the object to be dyed at the bottom of a pot. Cover the object with water. Add a 1:1 ratio of natural dye material and vinegar. Bring the pot to a boil then let simmer for 20 minutes. Once the pot is cool, strain. Handwash the object and let it air dry.
(fabric I dyed with blue pea flowers, saffron, and lavender)
Sea Witch by Wendy Joubert (1st Edition 2008) Pages 67-68