Dinner Garden provides a plethora of information about growing food for your table. According to them, "ginger grows outdoors in zones 10 and 11. If you grow it in other zones, you'll need to bring it inside if temperatures drop below 55 F degrees . The ginger rhizome won't grow grass in temperatures less than 75 F degrees. Between 55 F and 75 F degrees, the ginger will be in winter dormancy, and the grass will die. Temperatures less than 55 F will damage the ginger rhizome."
Dinner Garden writes:
To grow ginger plants, buy a small piece of ginger root at your local store. Look for fat pieces that have small nodes on them. You will need a large pot, about 12 inches tall by 12 inches wide. Fill the pot with potting soil mixed with compost. Make sure the potting soil has adequate drainage because ginger rhizomes don't like to sit in wet soil.
Place the ginger in 100 F water and let them soak for 8 hours. Plant 3 to 4 pieces of ginger in the pot. Bury them with about an 1/2 inch of soil, with the buds on top. Water regularly, but don't let the soil get soggy. If the ginger grass turns brown, you may be overwatering.
It can take up to 10 months before you can harvest the ginger. To use it, simply dig up one of rhizomes with the new sprouts, cut off the ginger you want, then bury the rest. The ginger will continue to grow. You can also cut off a larger piece and refrigerate it for use during the week.
Be sure to clip pieces of the ginger grass to use for cooking or to brew tea. You can do this at any point, so while you're waiting for your ginger root to grow, use that tasty ginger grass! For tea, steep the leaves in boiling water for five minutes. When using it for cooking, slice it thinly and only cook it briefly, like at the very end of your stir fry. The flavor of the grass is like very mild ginger with a hint of lemon, so it pairs well with almost anything.