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Giant Flat Dutch

Cabbage
Botanical illustration of Giant Flat Dutch
🌱 85d to harvest Rosette

Sweetly savory and richly aromatic, Giant Flat Dutch forms broad, flat heads with a dense, crisp bite and a beautifully tight lea…

Planting Schedule

Add Giant Flat Dutch to your garden to build a schedule and get reminders.

Crop Dates

MilestoneDate
Start IndoorsMay 18th
Last FrostJun 15th
Transplant / Sow OutdoorsJun 8th
Harvest BeginsSep 1st
Harvest EndsJul 15th

Crop Details

TraitValue
Days to Maturity85
Sun RequirementsFull SunFull sun
Growth HabitRosette
Support NeededNone
Planting DepthNormal
Germination Temp (°F)45
Min Soil Temp (°F)45
Min Night Temp (°F)32
Harden Off (days)6

Frequently Asked Questions


What pests or diseases commonly affect Brassica oleracea var. capitata (cabbage/Flat Dutch), and how can I prevent or treat them?
Watch for cabbage worms (imported cabbage moth/cabbage loopers) and aphids, which can skeletonize leaves and leave sticky honeydew. Hand-pick caterpillars early and spray with an approved Bt (Bacillus thuringiensis) when small larvae are present; for aphids, use a strong water spray and apply insecticidal soap if numbers persist. Also monitor for clubroot (swollen, deformed roots) and prevent it by avoiding replanting brassicas in the same spot and keeping soil slightly limed to a target pH of about 6.5–7 (if your soil test supports it).
How often should I water Brassica oleracea var. capitata during the main head-forming phase?
During the 6–8 weeks when heads are forming (roughly mid-season through about day 70), keep soil consistently moist but not waterlogged. Water deeply about 1–2 times per week to wet the root zone; increase to more frequent watering in heat or windy weather, and use mulch to reduce moisture swings that can cause loose heads. If the top 1 inch of soil dries out, it’s time to water again—steady moisture helps firm, tight heads by harvest (around day 85).
How can I tell when Brassica oleracea var. capitata (Flat Dutch) is ready to harvest?
Harvest when heads reach firm tightness—when you gently squeeze, they should feel solid and not springy. Typical harvest timing is about 85 days from sowing/transplanting to maturity, but use firmness as the final cue rather than the calendar alone. If outer leaves begin to yellow heavily or heads split from irregular moisture, harvest promptly to avoid quality loss.
Botanical illustration of Giant Flat Dutch

Sweetly savory and richly aromatic, Giant Flat Dutch forms broad, flat heads with a dense, crisp bite and a beautifully tight leaf wrap. The surface is finely textured and deeply veined, holding its shape through cool weather for dependable, satisfying harvests. Ideal for hearty cabbage dishes—shredding for slaws, simmering for braises, and fermenting for tangy kraut—this is a classic Flat Dutch performer with extra presence in the garden.

Sowing Tips

Transplant Conditions

Wait until soil reaches 45°F and nights stay above 32°F before moving outdoors. Harden off for 6 days first.

Expert Note

For oversized heads, keep temperatures evenly cool and avoid moisture swings after transplanting; consistent watering is key for large cabbage.