Fennel (Bitter) (Foeniculum vulgare var. vulgare) is a herbaceous essential oil with a sharp, anise-like, bitter aroma and a heart note. Steam distillation from seed, it is a versatile blending oil that pairs well with Lavender, Geranium, Rose. For topical use, keep dilution at or below 1.8%.
Bitter fennel with higher estragole (2-6%) than sweet fennel. Sharper camphoraceous-anise profile.
Aroma & character
Aroma
Properties
| Perfumery note | Heart |
| Aroma family | Herbaceous |
| Chemical family | Ether |
| Material type | Essential oil |
| Extraction | Steam distillation |
| Plant part | seed |
| Origin | France, Egypt, Hungary |
| Blending factor | 4 |
| Volatility index | 3 |
| Tenacity (hours) | 6.0 |
Safety & dilution
Higher estragole content than Sweet Fennel. Use with caution.
| Max topical dilution | 1.8% |
| Max facial dilution | 0.9% |
| Pregnancy | Not recommended |
| Nursing | Not recommended |
| Children | Not recommended for young children |
| Cats | Not recommended |
| Dogs | Generally suitable when properly diluted |
Safety flags
Evidence: Traditional — EODB: 2 GC-MS analyses (Foeniculum vulgare).
For education only — not medical or veterinary advice. Essential oils are not intended to diagnose, treat, cure, or prevent any condition. Always patch-test and consult a qualified professional before use during pregnancy, on children, with pets, or with a health condition.
Plan safe amounts with our essential oil dilution calculator.
Blends well with
Used in these blends
Frequently asked questions
What does Fennel (Bitter) smell like?
Fennel (Bitter) has a sharp, anise-like, bitter, camphoraceous aroma, classed as a herbaceous oil with a heart note.
What is the safe dilution for Fennel (Bitter)?
For topical use, keep Fennel (Bitter) at or below 1.8%, and 0.9% on facial skin. Always patch-test before wider use.
Is Fennel (Bitter) safe to use during pregnancy?
Fennel (Bitter) carries a pregnancy caution in our dataset and is not recommended during pregnancy. Consult a qualified healthcare provider before any use.
Is Fennel (Bitter) safe to use around children?
Fennel (Bitter) is not recommended for young children. Consult a professional before use.
Is Fennel (Bitter) safe around pets?
For cats — avoid; not considered safe; dogs — generally lower-risk when well diluted. Diffuse only in ventilated spaces and consult a veterinarian.
What does Fennel (Bitter) blend well with?
Fennel (Bitter) pairs well with Lavender, Geranium, Rose, Lemon (Cold Pressed), Blood Orange.