The ginger family (Zingiberaceae) contains over 700 species of ginger. What is called Hawaiian ginger describes a group of plants brought to the Hawaiian Islands by the early Polynesian settlers. These plants include both ornamental and edible gingers, and bloom in yellow, blue, pink, white and red flowers in an assortment of shapes and sizes. All Hawaiian ginger plants require warmth and moisture to thrive, and can be propagated by dividing their rhizomes.
Dig up the ginger rhizome by carefully cutting into the soil in a circle around it.
Divide the rhizome into pieces that contain at least one stem, and up to four.
Inspect the roots on each piece of rhizome. If they are small and not completely developed, cut the stem in half and dispose of the cut portion.
Dust the pieces of rhizome with fungicide.
Pour vermiculite into a pot, to within 1/4 inch of the rim, and water it until it is completely wet. Allow the pot to drain.
Create a 2-inch deep hole in the vermiculite and place the rhizome into it. Cover it with soil and place the pot in a well-lit area, out of direct sunlight, that remains above 50 degrees F.
Water the vermiculite to keep it moist, not saturated. You will know that the ginger rhizome has rooted when it produces new growth.