Playa California Salt Scalp Scrub Shampoo Meant to be rotated in weekly, the Playa California Salt Scalp Scrub Shampoo ($38) uses sea salt and tea tree oil to balance your scalp's natural oils plus work out dead skin cells and product buildup so your hair ends up cleaner when you're done. Image Source: sephora.com Playa California Salt Scalp Scrub Shampoo $38 from sephora.com Buy Now