The root chakra is the chakra located at your perineum, at the bottom of your spine. The root chakra is represented by the first color of the rainbow - red.
If your root chakra is healthy, it governs your basic instincts for survival. It controls your ability to maintain a home, to earn money to pay the bills, to have enough for your physical needs.
If this chakra is unhealthy, it can cause you to be greedy, feel needy, or unappreciative of what you do have. It can cause you to neglect the steps necessary to maintain your environment.
To help strengthen your root chakra, focus on the color red, which is found in ruby and garnet gemstones. Visualise a red flower opening.
If the problem is that you have too open at the root chakra, and are suffering issues of greed or domination in relationships, then it is time to balance the root chakra. See the red flower gently closing.
For an indepth read on the chakras look at Cyndi Dale's Complete Book of Chakra Healing.
The Seven Chakras