Cover the bottom of your slow cooker with a crockpot liner.
Fill your slow cooker about half full with water.
Add your natural dye ingredients to the slow cooker.
Turn your slow cooker on high and allow the water to heat up for about 3 to 4 hours until the dye liquid is fairly dark.
Using tongs or a slotted spoon, carefully remove the plant material from the slow cooker.
Ladle the dye liquid into cups or glass jars.
Carefully dip your hard-boiled eggs into the dye mixture. The longer they sit, the darker the color.
Using tongs or a slotted spoon, carefully remove the eggs from the dye mixture and place them in a colander to drain any excess dye.
Allow the eggs to cool completely before handling them.