I will simp[ly copy the referenced article for this topic as it is quite straight forward.
Examine the ginger plant blossoms and locate the ones that have turned brown or are wilting. Grasp the base of the stem with the dead or dying blossom. Use pruning shears to cut the stem off near the base of the plant. Ginger plant stems only produce one blossom before dying, so pruning these off makes the plant more attractive. Prune these stems continuously throughout the year each time a bloom fades.
Examine the lower leaves of the ginger plant and look for leaves that are brown or yellow. Remove these leaves by pulling them off the base of the plant with your fingers. Once leaves turn yellow or brown, they will not become healthy again. Removing these leaves directs the nutrients in the plant to the healthy parts.
Look for any sign of disease on the plant leaves, as indicated by black or grey spots. Ginger plants love moist soil and air but if overwatered can develop mildew. If you catch the mildew early enough, simply prune off the leaves or stalk using pruning shears, to prevent the disease from spreading.