Tradition
Good
avoidgood
4 chart entries: 4 recommend, 0 advise against.
All entries cite a source.
Dill
Anethum graveolens
Apiaceae
Fennel
Foeniculum vulgare
ApiaceaeCan you plant dill and fennel together?
No. Garden charts say that dill and fennel help each other, but the tests we found say otherwise. A shared bed gave about 13% less harvest than separate beds in one field trial. That rests on a single study, so treat it as a lead, not a rule.
Why the tests and the charts disagree
Less harvest from the same bed. In one field trial, a bed with both crops gave about 13% less harvest than the same space split into a dill bed and a fennel bed.
Sustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)Same family, shared pests. Dill and fennel are both in the Apiaceae family, so the same pests and diseases can move from one to the other.
Crop Rotation in the Vegetable Garden (Steil · 2025 · Iowa State University Extension and Outreach, Yard and Garden)Garden charts recommend it. 4 garden chart entries recommend growing them together. Charts pass on gardening tradition; they are not tests.
Sustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
What to plant with dill and fennel
Good neighbours of both, best tested first.
PepperWith dill: Draws in pest-eating insectsWith fennel: Less disease
What to keep away from dill and fennel
CarrotWith dill: Garden charts advise against it, not tested
The evidence in detail
For readers who want to dig in: every chart entry, study and yield trial behind the answer above, with the numbers.
Tradition, research and yield trials
Same family, shared pests and diseases. Both in Apiaceae: often susceptible to the same diseases and insects. Source: Iowa State University Extension and Outreach, Yard and Garden
Research
No papers found on this pair.
Yield trial
Bad
0.54
0.42
Dill gains more. Partial LER is each crop's share of the yield it would give alone.
1 field trial. Published LERs lean high.
Myth busted
What happens above and below ground
Each animation illustrates a mechanism a study reported for this pair. Pick a card to focus on it.
Everything at once.
Companion plants for both dill and fennel
Plants that are good neighbours of each. Biggest harvest gain first; each cell links to the evidence for that pair.
| Plant | With dill | With fennel |
|---|---|---|
| Pepper | Draws in pest-eating insectsField trial, 1 study. Charts: not listed.Evidence for dill and peppers | Less diseaseGreenhouse or pot trial, 1 study. Charts: not listed.Evidence for fennel and peppers |
The evidence, with sources
- BadLER 0.87field trialItaly, 2000-2002; Replacement design; median LER 0.87 over 3 treatment(s) · partial LER Dill 0.54, Fennel 0.42Sustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
- GoodDill helps FennelDill: helps fennelSustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
- GoodFennel helps DillDill: helped by FennelSustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
- GoodFennel helps DillFennel: helps DillSustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
- GoodDill helps FennelFennel: helped by DillSustainable production of fennel and dill by intercropping (Carrubba · 2008 · Agronomy for Sustainable Development)
- Both in Apiaceae: often susceptible to the same diseases and insectsCrop Rotation in the Vegetable Garden (Steil · 2025 · Iowa State University Extension and Outreach, Yard and Garden)
All neighbours of dill and of fennel, or every pair at once in the companion planting chart.
Have you grown dill and fennel together?
Tell other gardeners what happened: spacing, pests, harvest, or ask a question. Reader notes are not checked by us and do not change the verdicts on this page.