Plants have been used to dye fabric for centuries. The process is easily replicated at your kitchen stove or even a hotplate in a classroom. Select berries and vegetables for dyeing at the market, pick them in the garden or find them growing as wildflowers or weeds. Some options are blueberries for a bluish-purple color, beets for dark red, onion skins for orange, or marigolds for yellow. You may wish to have several large pots containing different plant dyes to experiment with the variety of colors produced. Use your homemade dye to color cotton fabric or to dye a cotton T-shirt -- natural fabrics will work best.
Pull the rubber gloves onto your hands to prevent staining.
Chop the blueberries finely on the cutting board with the knife. Place the chopped blueberries in the pot.
Add 4 cups water to the pot.
Place the pot on the stove or hotplate and bring the blueberry and water mixture to a boil. Simmer for an hour.
Place the strainer over the bowl and pour the blueberry and water mixture through the strainer. Discard the blueberries caught by the strainer. The dyed water that passes into the bowl is ready to use or to store in a glass jar.
Use any quantity of fruit, vegetable, nut, leaf or root to make dye. Whatever quantity you use, the water added must be twice as much as the plant material used. If you decide to dye fabric with your homemade dye solution, pretreat the fabric with a fixative to help it absorb the dye. If using a dye made of berries, treat the fabric with a salt water solution made of 1/2 cup salt and 8 cups water. For all other dyes, treat the fabric with a solution made of 4 parts cold water and 1 part vinegar.
Use plants that you know are safe to boil, such as fruits and vegetables. If you wish to experiment with different plants, check with poison control first.