How to Make Natural Blue Food Dye

There are several ways to make natural blue food dye.

Method 1: 

1 cup blueberries  +  hot water

Pulverize in blender

let sit for 10 minutes

Strain using mesh sieve or cheesecloth

Method 2: 

1 cup blackberries  +  hot water

Pulverize in blender

Let sit for 10 minutes

Strain using mesh sieve or cheesecloth

Method 3:

1/2 head red cabbage, no stems, cut into chunks
Water (enough to cover cabbage)

Simmer 10 minutes
Strain

Add baking soda (1/4 tsp at a time) OR green tea until the purple solution turns blue

Source:

http://www.foxnews.com/leisure/2013/03/27/9-ways-to-dye-eggs-naturally/

http://shine.yahoo.com/spring-celebrations/8-ways-organic-diy-food-coloring-220600943.html