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) essential oil 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) 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.