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A dark beard is considered desirable by many men, especially those who are going gray. However, to others it may present an inconvenience. Dark beards are more pronounced than light ones and thus need to be shaved more often. For those who don't like to shave this can be a hassle. There are other reasons to lighten your beard, such as making it match the hair on your head. Beard hair is more course than head hair and reacts differently to dye. But with the right technique, you will soon have your beard looking just the way you want it to.

Prepare the rhubarb. Cut up a rhubarb and place it in a pot. Cover it with water, then bring the water to a boil for 30 minutes. Strain the liquid, and then pour it into a bottle. The bottle should be no more than half filled.

Complete the mixture. Pour equal parts hydrogen peroxide, lemon juice and lavender oil into a bowl and mix them. Pour the mixture into the bottle. Place the bottle in the refrigerator at least 30 minutes before using it.

Apply the mixture. Rub the solution over your beard. Make sure your hair is saturated. Once the liquid has dried, wash it off. Repeat the application daily until your beard has reached the desired color.