The first time you see blue tansy oil, it looks fake. It's a deep, inky blue, the kind of color you'd expect from food dye. But nothing's added. The color comes from the plant, and how it gets there is one of the more interesting stories in your bathroom cabinet.
What it is
Blue tansy oil is an essential oil from Tanacetum annuum, a small yellow-flowered plant that grows around the Mediterranean, mostly in Morocco. It's sometimes called Moroccan blue chamomile, because it's related to chamomile and shares some of the same compounds.
On an ingredient list, it appears as Tanacetum Annuum Flower Oil.
Why it's blue
The flowers aren't blue. They're yellow. The blue appears during steam distillation, when heat turns a natural compound in the plant into chamazulene, a deep blue molecule. German chamomile goes through the same change, which is why its oil is blue too.
Chamazulene is also why blue tansy is known for a calming feel on skin, and why it shows up in products for skin that looks red.
Why the blue fades
Chamazulene doesn't love light or air. Over time, and faster in a clear bottle on a sunny windowsill, blue tansy shifts from blue toward green. That's why you'll usually find it in amber or dark glass.
In our oil, vitamin E and rosemary extract are there for the same reason: they slow oxidation, which helps keep the color bright and the oils fresh. They look after the formula, not your skin.
Blue tansy is not common tansy
"Tansy" on its own usually means Tanacetum vulgare, common tansy, a different plant entirely. It isn't used the same way in products for skin. If you're reading a label or buying the oil on its own, look for the full name Tanacetum annuum.
Will it turn my skin blue?
No. A few drops spread thin enough that the color disappears.
How it's used
Blue tansy is strong, so it's almost always a small part of a blend rather than the main ingredient. In Blue Tansy Dry Oil, it's paired with:
- Bisabolol, a calming ingredient best known from chamomile. Together, they help reduce the look of redness.
- Manuka oil, a traditional New Zealand oil chosen for blemish-prone skin.
- A fast-drying base of C13-15 alkane, caprylic/capric triglyceride, squalane, jojoba, and meadowfoam, so the whole thing dries down in about a minute instead of sitting on your face.
A few practical notes
- Patch test first. Blue tansy is an essential oil, and some people react to essential oils. Try a drop on your inner arm and wait a day.
- Keep it away from your eyes.
- If you're pregnant or nursing, ask your doctor before using products with essential oils.
- Store it away from sun and heat so the color lasts.