Parsnip plant

Parsnip growing profile.

Parsnip Companion Plants

What may help, what can compete, and where the evidence is still uncertain.

Parsnip Pastinaca sativa

Cool-season vegetable in the carrot family. View plant profile →

Quick answer

No reviewed study supports a specific beneficial companion for parsnip yet. 1 popular pairing has no verified relationship, which is not the same as safe or harmful.

Every status below has a direction, mechanism, context and source. "No verified relationship" means we looked and found nothing usable; the planner then evaluates spacing, light, water and timing normally. How we classify evidence →

1 records

No verified relationship (1)

Zero score and an honest unknown state. Spacing, light, water and timing are evaluated normally.

No verified relationship: we did not find a source that establishes a benefit or harm for these pairs. This is not the same as "compatible".

OnionAllium cepaNo verified relationshipOther Parsnip and Onion affect each other (mutual)Spring–Fall · arrangement unspecifiedUnknown Review: August 15, 2026
Why?

Claim. We did not find a source that establishes a benefit or harm between parsnip and onion.

Mechanism. None documented.

Conditions. Planted together Both plants must be present at the same time.

Applies when. The planner evaluates spacing, light, water and timing normally.

Limitations. No relationship documented.

Evidence. Unknown: No source meeting the inclusion rules. (none).

Sources. University of Minnesota Extension 2023

Reviewed August 15, 2026 by Garden Planner editorial team (pending independent horticultural review). Record parsnip--onion--other v1. Request a correction.

Example layout for parsnip

No supported or conditional relationship specifies a layout. Space parsnip at 8–10 cm and plan by light, water and timing.

Side view of parsnip (30–45 cm) beside typical companions, showing canopy, support, shade and access.

When these companions overlap

Bed occupancy in Portland, Oregon (estimates). A relationship only matters while both plants are present.

Parsnip
Onion22 wk overlap
Overlap in weeks
Onion22 weeks

Crop rotation guidance

Rotation is about what occupied the bed in previous seasons and is calculated separately from the live companion relationships above.

Rotate parsnip on a 2-year cycle with other carrot family crops (Carrot, Celery, Parsley, Cilantro, Dill). Shared risks: carrot rust fly, Alternaria leaf blight, parsley worm (swallowtail caterpillar).

Crop rotation hub · Apiaceae family page

Physical and resource fit

No significant light, water, pH or sprawl conflicts with the listed companions at recommended spacing.

Fit checks come from plant attributes and apply even when a pairing has a positive claim.

Community observations (anecdotal)

These reports come from gardeners and are not reviewed evidence. Results vary with soil, climate and practice. Community data never changes an evidence tier or a planner score.

Reports for parsnip: 0 (community submissions open in a later phase; drafts are stored only on your device).

Community-submitted photo area (moderated) with context fields: region, season, layout, varieties, outcome.
Record an observation

Evidence summary and sources

Reviewer: Garden Planner editorial team (pending independent horticultural review). Status counts on the Companions A–Z page are derived from these records. Corrections.

Related

Visual evidence on this page

Documentary and illustrated views distinguish identification, measured layout, seasonal overlap, mechanisms, coexistence examples, and community observations. Captions state what each visual can and cannot establish.

Our Methodology & Sources

We synthesize peer-reviewed research, university extension publications, and trusted horticulture resources. Our evidence levels help you understand how strong the science is behind the guidance.

Evidence tiers

Supported evidenceConsistent results from multiple robust studies
Traditional claimHistorical use reported, limited scientific support
Context dependentMixed or variable results across conditions
No verified relationshipNo reliable evidence identified

Primary source types

  • Peer-reviewed journal articles
  • University extension publications
  • Government & research institute reports
  • Systematic reviews & meta-analyses

Last updated

August 24, 2026

Learn more about our approach