With these dry winter days I’ve been finding I’ve been reaching for this fragrant hair serum a lot recently—whenever my hair needs a bit of smoothing, added shine, and general oomph. I’ll run a pump or two through my hair from about the ears down and it leaves my hair smoother, easier to manage, and just generally looking better—without weighing it down. It doesn’t hurt that it also smells fantastic, leaving me walking around in a bit of a rose-scented cloud directly after use (it’s crazy easy to make). If you’ve got relatively fine hair that needs a bit of a kick in the winter, this serum is for you!

How to Make Smooth & Shine Hair Serum

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I first made this hair serum back in September thinking it would be a mist. It had other ideas. Polyquaternium 7, the primary conditioning agent in this formula, is super viscous, and even at just 2% it yielded an end product that didn’t so much mist as aggressively jet out of a mister top. No worries—it still applies beautifully when worked through the hair with your hands, and I find it’s easier to monitor exactly how much product you’re using when you have to look at it in your palm before you apply it to your hair.

 

How to Make Smooth & Shine Hair Serum

How to Make Smooth & Shine Hair Serum

I’ve included two conditioning ingredients—the previously mentioned Polyquaternium 7 and some cetrimonium chloride. I really fell in love with Polyquaternium 7 last year when I used it to make my Foaming Shaving Cream. The skin and hair feel is just… divine. I cannot get over how utterly touchable it leaves everything it touches! Cetrimonium chloride helps with detangling and helps improve rinse-out as it’s also a surfactant. The usage rate is quite low as that’s the maximum recommended usage rate for leave-on products.

How to Make Smooth & Shine Hair Serum

How to Make Smooth & Shine Hair Serum

Up next, panthenol: how I love thee. Panthenol (AKA vitamin B5) is a great hair moisturizer, making the hair softer and shinier, and making it more elastic. Some vegetable glycerine also further increases the moisturizing properties of the serum.

How to Make Smooth & Shine Hair Serum

How to Make Smooth & Shine Hair Serum

I also included a bit of Cromollient SCE (INCI: Di-PPG-2 Myreth-10 Adipate). I first used it last year in a cleansing oil, but the fact sheet on has a section all about how amazing it is for hair. It helps with detangling, makes wet combing easier, and adds some of the benefits of oil + hair without worrying about solubilizing it into an otherwise watery formula.

How to Make Smooth & Shine Hair Serum

How to Make Smooth & Shine Hair Serum

The scent comes entirely from our hydrosol; I’ve gone with rose because I am positively addicted to rose, but you could easily use something else instead. I’ve also provided guidelines for using a fragrance or essential oil instead instead—those are in the handy “Substitutions” section at the end of the recipe!

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Smooth & Shine Hair Serum

22.125g | 73.75% distilled water
6g | 20% rose hydrosol
0.6g | 2% vegetable glycerine (USA / Canada)
0.6g | 2% Polyquaternium 7 (USA / Canada)
0.075g | 0.25% cetrimonium chloride (30% solution) (USA / Canada)
0.15g | 0.5% panthenol powder (vitamin B5) (USA / Canada)
0.3g | 1% Cromollient SCE
0.15g | 0.5% Liquid Germall Plus™ (USA / Canada)

Weigh the everything into a small heat-resistant glass measuring cup or directly into a 30mL/1oz bottle with a treatment pump (a dropper top will also work). Stir or cap & shake to combine. If you didn’t make the serum directly in your bottle, transfer it to the bottle. That’s it!

To use, dispense a single pump into your palm, rub your hands together, and then run your hands through your hair, taking care not to deposit too much product in any one place. Repeat as necessary. That’s it!

Shelf Life & Storage

Because this serum contains water, you must include a broad-spectrum preservative to ward off microbial growth. This is non-optional. Even with a preservative this project is likely to eventually spoil as our kitchens are not sterile laboratories, so in the event you notice any change in colour, scent, or texture, chuck it out and make a fresh batch.

Substitutions

As always, be aware that making substitutions will change the final product. While these swaps won’t break the recipe, you will get a different final product than I did.

  • As I’ve provided this recipe in percentages as well as grams you can easily calculate it to any size using a simple spreadsheet as I’ve explained in this post. As written in grams this recipe will make 30g.
  • To learn more about the ingredients used in this recipe, including why they’re included and what you can substitute them with, please visit the Humblebee & Me Encyclopedia. It doesn’t have everything in it yet, but there’s lots of good information there!
  • If you’re like to use a different preservative, please review this page.
  • You can use a different hydrosol for a different scent.
  • Sodium lactate or propanediol would both be good alternatives for the vegetable glycerin
  • You could use honeyquat instead of Polyquaternium 7, but I don’t really recommend it—mostly because honeyquat smells really, really fishy and rather gross while Polyquaternium 7 smells like nothing
  • You can replace the cetrimonium chloride and/or panthenol with more water. This is not a substitution but will keep the recipe in balance.
  • You could try a different water soluble oil like Olivem 300 or water soluble shea butter in place of the Cromollient SCE.
  • If you’d like to use a fragrance or essential oil instead of a hydrosol for scent simply use 93.25% water and include 0.5% fragrance or essential oil; I’ve found the Cromollient SCE in the formula will solubilize the fragrance. If you are using something other than Cromollient SCE this may not hold true.

How to Make Smooth & Shine Hair Serum

How to Make Smooth & Shine Hair Serum