Rinse the rice to get rid of excess starch. Put it into a heavy bottomed pot with a tight fitting lid. Add the water, ginger, cardamom, and salt and give it a good stir. Bring it to a boil, reduce the heat to a simmer, cover, and cook gently for about 15 minutes. You will see holes poking through the rice and most of the water should be absorbed. Let the rice stand off the heat, covered, for about 5 minutes. Remove the ginger and discard, fluff the rice and serve.