Garden PlannerEvidence-aware. Garden with confidence.
Entire healthy mature cabbage plant in a real garden bed, showing growth habit and scale.Primary identification image. 30–45 cm tall, 45–60 cm wide at maturity.

Cabbage

Brassica oleracea var. capitata L.

Also called: Head cabbage, Savoy cabbage, Red cabbage

Family
Brassicaceae
Season
Cool-season biennial grown as an annual
Best grown in
Portland, Oregon

A heavy-feeding, hardy head crop transplanted in early spring and again in summer for autumn. The best-studied crop in companion research.

Add to plan View companions Calendar

Life cycle & growth stages

  1. 1. SeedSow indoors 6–8 weeks before last frost.
  2. 2. SeedlingEmerges in 5–10 days; grow cool and bright.
  3. 3. TransplantSet out 2–4 weeks before last frost; firm in well.
  4. 4. Mid-growthLarge outer leaves form a rosette 45–60 cm wide.
  5. 5. HeadingCentral leaves fold inward to form the head.
  6. 6. Harvest readyHead firm when squeezed.
  7. 7. HarvestCut at the base; leave stump for small secondary heads.

Growth stages are ordered chronologically; timing varies with cultivar, temperature, light and care.

Planting calendar for Portland, Oregon

Start indoors 6–8 weeks before last frost; transplant 1–4 weeks before last frost; 60–100 days to maturity from transplant. Windows are derived from the region's average frost dates (last Apr 5, first Nov 5) and are estimates until you confirm your own dates in the calendar.

CabbageBrassica oleracea var. capitata
PlantStart indoorsDirect sowAutumn sowTransplantTendHarvest
CabbageFeb 8–Feb 22 (estimate)—Jul 30–Aug 13 (estimate)Mar 8–Mar 29 (estimate)Mar 29–May 7 (estimate)May 7–Jul 28 (estimate)
  • Start seeds indoors: Feb 8 – Feb 22
  • Transplant outdoors: Mar 8 – Mar 29
  • Tend and monitor: Mar 29 – May 7
  • Harvest: May 7 – Jul 28
  • Autumn sowing: Jul 30 – Aug 13

Spacing & support

In-row 45–60 cm; rows 60–90 cm. Planner footprint: 2 cells of 30 cm.

Side-profile diagram of mature cabbage: canopy 30–45 cm tall, 45–60 cm wide, medium root zone, support and harvest-access envelope.

Soil & water

Soil
Firm, fertile, moisture-retentive loam
pH
6.5–7.5
Fertility
high
Water
Consistent water; sudden water after drought splits heads.
Frost
hardy; tolerates frost

Support & training

No support structure needed.

Cabbage mid-season before harvest, showing branching, vining, rosette or upright habit and space occupied.

Harvest signs

  • Head firm and dense when squeezed
  • Outer wrapper leaves begin to curl back
  • Cut before heads split after rain
Cabbage at harvest readiness, showing the visual cues: head firm and dense when squeezed; outer wrapper leaves begin to curl back.

Common problems

Pests: cabbage white caterpillars, cabbage root fly, diamondback moth, flea beetles, cabbage aphid

Diseases: clubroot, black rot, downy mildew

Appearance alone is not a diagnosis; confirm with a regional extension guide.

Side-by-side: healthy cabbage leaf or fruit and an example of clubroot.

Container growing

  • Minimum 20 L (30 cm deep)
  • Use quality potting mix and water more frequently
  • Choose compact cultivars.
Mature cabbage in a correctly sized container (20 L or more) with drainage visible.

Companion overview

16 reviewed relationship records (evidence: high).

Avoid or separate

White clover

Traditional claims only: Lavender, French marigold, Mint, Nasturtium, Rhubarb, Sage, Thyme, Tomato.

1 popular pairing reviewed with no verified relationship.

Full companion profile

Crop rotation

Avoid planting cabbage or other cabbage family crops in the same spot for 3 years. Rotation is about previous seasons, not about live neighbours.

Year 1Year 2Year 3BrassicaceaeOther familyOther familyback after 3+ years

Shared risks in Brassicaceae: clubroot, cabbage root fly, cabbage white caterpillars.

Crop rotation hub

Sources, reviewer & update

Sources

Reviewer: Garden Planner editorial team (pending independent horticultural review)

Last reviewed: August 15, 2026 · version 1

Found an error or have feedback? Let us know.

Growing cabbage

Cabbage is started indoors 6–8 weeks before the last frost and transplanted 2–4 weeks before it; the plants tolerate frost but heads split and bolt in summer heat, so spring crops should mature before the hottest weeks. A second planting in midsummer gives autumn and winter heads.

Cabbage seed beside a ruler or coin for scale.
Cabbage seedling at cotyledon and first-true-leaf stage, in soil, distinguishable from common weeds.
Cabbage mid-season before harvest, showing branching, vining, rosette or upright habit and space occupied.

Cabbage is one of the few vegetables with a real body of companion and intercropping research. Undersowing with clover and surrounding with non-host plants disrupts egg-laying by cabbage root fly and other pests (the "appropriate/inappropriate landings" effect), and a 2023 meta-analysis found substantially lower pest injury from intercropping alongside a modest average yield cost from competition.

Two or more mature cabbage plants with a tape measure showing in-row spacing (45–60 cm).
Cabbage flower detail or bolting stage.
Immature leaves of cabbage developing on the plant.

Cabbage white caterpillars, cabbage root fly, diamondback moth, flea beetles and aphids are the routine pests; fine mesh over the crop from transplanting is the simplest protection. Clubroot persists in soil for many years, so rotate all brassicas as one group and keep pH near 7.

Edible parts and safety

Edible: leaves (head).

Hands or tool harvesting cabbage correctly (cut, pull, twist or pick) without damaging the plant.

Pests and diseases

Common pests: cabbage white caterpillars, cabbage root fly, diamondback moth, flea beetles, cabbage aphid. Common diseases: clubroot, black rot, downy mildew. These vary by region; a photograph is an example, not a diagnosis. See the pest and disease guides and your local extension service.

cabbage white caterpillars on cabbage, with a wider damage-context view.

Timeline

Season timeline for cabbage: sowing, transplanting, flowering, harvest and bed occupancy aligned to frost dates.Text alternative: Start seeds indoors Feb 8–Feb 22; Transplant outdoors Mar 8–Mar 29; Tend and monitor Mar 29–May 7; Harvest May 7–Jul 28; Autumn sowing Jul 30–Aug 13.

Related plants

See also: Brassicaceae family page · crop rotation · regional calendar · guides

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