Can I grow ginger here in Seattle?
Culinary ginger, Zingiber officinale, can be grown in a container. As long as you are not hoping to grow it outdoors year-round or to harvest ginger root, you should have good success. A webpage (no longer available) from the National Botanic Garden of Wales has useful instructions on doing this:
“Look for a ginger root with green, bumpy buds. Half bury the root in compost. A mushroom container makes an excellent pot. Put the pot in a warm, sunny place indoors. Keep the compost damp. When the buds start to shoot keep the plant in a warm light place, but not in full sun. A north facing window is good.
Keep the plant warm and watered in spring and summer. In the autumn it will die down, so keep the compost dry until it starts to grow again in spring. It may need watering in spring to start it shooting again. If you are lucky it may flower in July in the second year! The flower spike is worth waiting for. A healthy ginger will grow to a height of 1 metre (3 feet).”
Sunset Western Garden Book (2007) lists this plant as a perennial but not an outdoor plant in the Pacific Northwest. (Ginger grows in tropical areas, and is commercially grown in the U.S. in Hawaii.) They recommend buying fresh roots at the grocery store in early spring. Cut the rhizomes into 1 to 2 inch-long sections, making sure each has well-developed growth buds. Let the cut ends dry, and then plant just below the surface of rich, moist soil. Water with caution until top and root growth begin. Feed once a month. Plants are dormant in winter. If you are growing them to harvest the rhizomes, this can be done at any time of year, but it will take several months for them to attain any size.