Lathering shampoo into your mane or spritzing on hair spray is simple enough, but hair serums get a little trickier because, depending on the type of serum (and there are many), application rules vary. Read on to learn how to get the most out of your hair serum for longer, lusher locks and overall hair wellness.

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Hair Serum 101

Hair serums make up a concoction of vital nutrients that tend to come in higher, more potent concentrations. These ingredient-packed elixirs have the ability to work beyond the surface of the hair and scalp and penetrate deep enough to work from the inside out. (That’s not to say that they don’t help the surface and provide instant results.)

The Different Types of Hair Serums

Whether you’re worried about ultra-dry strands, uncontrollable frizz, or would like to encourage hair growth, there’s a serum for that. You have plenty of options to choose from, including hair serums for moisture, for shine, and for growth, including our GRO+ Volumizing Hair Serum, which targets hair thinning and hair loss with natural active ingredients. In fact, users reported 76% less shedding and 50% greater density in as little as four months.

How to Prep Your Hair and Scalp for a Serum

To reap the maximum benefits from a hair serum, thoroughly cleanse and condition your hair as you normally would. Serums aren’t as effective if your scalp and hair aren’t clean and ready to absorb all the nourishing goodness.

How to Apply Hair Serum

  • Determine if your hair should be damp or dry: Read the label first; it should tell you if your hair should be wet or dry. For serums that work best on damp hair, celebrity hairstylist Alex Brown [1] suggests applying one to two pumps of hair serum directly onto your strands before drying your hair, especially blow-drying, to get the most out of it. She also suggests applying half a pump on your strands once your hair is dry for extra protection, added shine, and a glossier finish. In the case of our GRO+ hair serum, it’s meant to be applied onto fully dry or towel-dried strands, and it goes directly onto your scalp.
  • Do scalp serums correctly. For hair serums meant to be applied directly to your scalp, use a fine-tooth comb to part your hair evenly into different sections around one to two inches apart. Apply two to four drops on the exposed scalp area (not all on the same spot). Use your clean fingers to rub the serum in. Don’t rush this part -- think of it as a mini-massage! 
  • Know your limit: The last thing you want to do is overapply a product. Sure, shiny strands can be tempting, but using globs of product won’t work in your favor, and will lead to heavy hair. Hairstylist Giovanni Giuntoli [2] says if your hair is on the thinner side, go for a pea-sized amount; for thicker hair types, bump it up to a quarter-sized amount.
  • Don’t rinse it out: Think of serums as part of your styling routine, not your wash routine. As we mentioned above, proceed to dry and style your hair as usual after applying your hair serum. It shouldn’t be rinsed out until the next time you wash your hair.
  • Use daily or every few days: Depending on your needs, hair and scalp serums can be applied daily or every two to three days. If you’re looking to wash your hair less and are using a clarifying serum, you likely don’t have to use it everyday. Overusing a moisturizing serum might make your hair feel heavy and greasy (but if it’s feeling dry, reapply it after a few days). However, when it comes to scalp and hair growth serums, daily application is likely the preferred method. Our GRO+ serum should be applied every day to see the most growth and achieve the best results at the end. Hair growth serums aren’t designed to weigh down hair as they penetrate the scalp, unlike moisturizing serums that tend to stay on the surface.