Shampoos, scalp treatments, masks and dry shampoos for hair that gets greasy quickly. The basics: a shampoo that cleanses without stripping, such as Cut by Fred's Vegan Detox Shampoo, Innersense's Pure Harmony Shampoo or Whamisa's fermented-seed shampoo for oily hair, followed by a scalp treatment (Vegan Scalp Potion, Whamisa's scalp tonic). Between washes: Innersense's Refresh Dry Shampoo or Cut by Fred's Dry Shampoo Brune.