Hybrid

Haku

Brassica rapa var. pekinensis

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Very good performance along the Eastern Seaboard, as well as in Arizona and California. Heads avg. 11" tall and 5 1/2-6 lb. Our most heat tolerant, tipburn tolerant, and adaptable variety.

Harvest

55d

Days to harvest

📅

Sun

Full sun to part shade

☀️

Zones

5–9

USDA hardiness

🗺️

Height

3 feet

📏

Planting Timeline

Zone:

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Start Indoors

Transplant

Direct Sow

Harvest

Start Indoors

Transplant

Direct Sow

Harvest

Showing dates for Haku in USDA Zone 7

All Zone 7 brassica →

Zone Map

Click a state to update dates

Haku · Zones 5–9

What grows well in Zone 7? →

Growing Details

Difficulty

Easy

Spacing18-24 inches

SoilWell-drained loam, pH 6.0-7.5

WaterHigh — consistent moisture needed

SeasonWarm season annual

FlavorMild, tender, and slightly sweet with crisp leaves; less peppery than storage cabbages.

ColorLight green

Size11"

Zone-by-Zone Planting Calendar

Zone	Indoor Start	Transplant	Direct Sow	Harvest
Zone 3	March – April	May – June	May – June	June – October
Zone 4	March – April	May – June	April – June	June – October
Zone 5	February – March	April – May	April – May	June – November
Zone 6	February – March	April – May	April – May	May – November
Zone 7	February – March	April – May	March – May	May – November
Zone 8	January – February	March – April	March – April	April – December
Zone 9	January – January	February – March	February – March	March – December
Zone 10	January – January	February – March	January – March	March – December
Zone 1	April – May	June – July	June – July	July – September
Zone 2	April – May	June – July	May – July	July – September
Zone 11	January – January	January – February	January – February	February – December
Zone 12	January – January	January – February	January – February	February – December
Zone 13	January – January	January – February	January – February	February – December

Succession Planting

Direct sow Haku every 14–18 days from late March through early May for a spring run, then stop — napa bolts quickly once daytime highs push past 80°F and nights stop cooling down. Resume in late August for a fall succession, counting back 55 days from your expected first frost to set your last sow date. The fall window tends to produce cleaner, tighter heads, though NC State Extension cautions that flea beetle and looper populations run higher in fall after building up all summer — have row cover ready from day one.

Complete Growing Guide

Very good performance along the Eastern Seaboard, as well as in Arizona and California. Heads avg. 11" tall and 5 1/2-6 lb. Our most heat tolerant, tipburn tolerant, and adaptable variety. According to Johnny's Selected Seeds, Haku is 55 days to maturity, annual, hybrid (f1). Disease resistance includes Club Root, Downy Mildew.

Light: Full sun (6 or more hours of direct sunlight a day), Partial Shade (Direct sunlight only part of the day, 2-6 hours). Soil: Clay, Loam (Silt), Sand. Soil pH: Acid (<6.0), Neutral (6.0-8.0). Drainage: Good Drainage, Moist. Height: 0 ft. 10 in. - 2 ft. 0 in.. Spread: 1 ft. 0 in. - 2 ft. 0 in.. Spacing: 12 inches-3 feet. Growth rate: Medium. Maintenance: Medium. Propagation: Seed, Stem Cutting. Regions: Coastal, Mountains, Piedmont.

Harvesting

Haku reaches harvest at 55 days from sowing per Johnny's Selected Seeds. Expect 11" at peak. As an annual, harvest continues until frost ends the season.

The fruits dry and split when ripe.

Color: Brown/Copper, Green. Type: Siliqua. Length: > 3 inches.

Garden value: Edible

Harvest time: Fall, Summer

Bloom time: Spring, Summer

Edibility: The foliage is edible raw or cooked but when cooked can emit an unpleasant odor.

Storage & Preservation

Haku cabbage keeps longest in cold, humid storage at 32–40°F with 95% relative humidity—a root cellar or refrigerator crisper drawer works well. Wrap heads loosely in plastic to prevent moisture loss. Expect 2–3 months of fresh storage if harvested at full maturity and kept undamaged. For preservation, blanch shredded Haku for 2 minutes before freezing in airtight containers; it holds well for up to 8 months. Fermentation is excellent—slice cabbage, salt at 2–3% by weight, and pack into jars under brine for a crisp, tangy product ready in 1–4 weeks. Dehydrating thin slices at 130–140°F yields shelf-stable chips. This variety's tender, pale leaves ferment faster than storage cabbages and develop mild flavor quickly, making it ideal for quick-turn ferments rather than long aging.

History & Origin

Haku is an F1 hybrid developed through controlled cross-pollination. Listed in the Johnny's Selected Seeds catalog.

Brassica is a genus of plants in the cabbage and mustard family (Brassicaceae). The members of the genus are informally known as cruciferous vegetables, cabbages, mustard plants, or simply brassicas. Crops from this genus are sometimes called cole crops—derived from the Latin caulis, denoting the stem or stalk of a plant.

Advantages

+Excellent heat tolerance makes Haku ideal for warm season growing
+Fast 55-day maturity allows multiple plantings per season
+Superior tipburn resistance reduces crop loss from physiological disorder
+Outstanding adaptability performs well across diverse US growing regions
+Reliable heading produces consistently sized 5.5-6 lb compact heads

Considerations

-Limited performance outside Eastern Seaboard, Arizona, and California regions
-Susceptible to cabbage worms and other common Brassica pests
-Requires consistent moisture to prevent bolting and quality decline

Companion Plants

Nasturtiums and marigolds do real work here — nasturtiums act as a trap crop that pulls aphids off your napa, while Tagetes patula specifically has documented nematode-suppressing properties in the root zone. Dill attracts parasitic wasps that target Trichoplusia ni larvae, and onions' sulfur compounds help mask the brassica scent that flea beetles key in on. Tomatoes are the one to avoid: they compete aggressively for the same calcium and moisture that a heading napa needs over its 55-day run, and the root chemistry doesn't do your brassicas any favors. Pole beans can physically shade out a developing head — keep them on the far side of the bed.

Plant Together

Nasturtiums

Acts as trap crop for aphids and flea beetles, protecting brassicas from these pests

Marigolds

Repels cabbage worms, aphids, and other brassica pests with natural compounds

Dill

Attracts beneficial insects like parasitic wasps that control cabbage worms

Onions

Repels cabbage maggots, aphids, and flea beetles with sulfur compounds

Lettuce

Provides ground cover and efficient space usage without competing for nutrients

Carrots

Different root depths prevent competition while carrots benefit from brassica soil conditioning

Celery

Repels cabbage worms and provides natural pest deterrent through aromatic compounds

Spinach

Cool-season companion that maximizes garden space without nutrient competition

Keep Apart

Strawberries

Brassicas can stunt strawberry growth and negatively affect fruit production

Tomatoes

Allelopathic effects inhibit brassica growth and both compete for similar nutrients

Pole Beans

Can inhibit brassica growth and create too much shade for optimal development

Nutrition Facts

Calories

31kcal(2%)

Protein

2.57g(5%)

Fiber

2.4g(9%)

Carbs

6.27g(2%)

Fat

0.34g(0%)

Vitamin C

91.3mg(101%)

Vitamin A

8mcg(1%)

Vitamin K

102mcg(85%)

Iron

0.69mg(4%)

Calcium

46mg(4%)

Potassium

303mg(6%)

Per 100g serving. % Daily Value based on 2,000 calorie diet. Source: USDA FoodData Central (FDC #747447)

Pests & Disease Resistance

Resistance

Club Root (Intermediate); Downy Mildew (Intermediate)

Common Pests

Cabbage looper, flea beetles, diamondback moths, aphids

Diseases

Clubroot, black rot, fusarium wilt

Troubleshooting Haku

What you'll see, why it happens, and what to do about it.

Seedlings collapse at soil level — stems look pinched or water-soaked, then turn black and shrivel within a day or two of germination

Likely Causes

Damping off (Pythium or Rhizoctonia spp.) — fungal pathogens that thrive in cold, wet, poorly-drained soil
Overwatering or sowing too densely, which keeps the soil surface wet and cuts airflow around stems

What to Do

1.Pull and discard affected seedlings immediately — don't let them sit and spread spores
2.Let the soil surface dry slightly between waterings; bottom-watering trays is better than overhead watering for starts
3.Next round, start in fresh sterile seed-starting mix and make sure trays drain freely within 30 minutes of watering

Leaves show small, ragged holes — mostly along the edges and across the blade — starting a week or two after transplant

Likely Causes

Flea beetles (Phyllotreta spp.) — tiny, fast-jumping beetles that chew shotgun-pattern holes, worst on young transplants
Cabbage looper (Trichoplusia ni) — larger, irregular holes, often with green caterpillars visible on the undersides of leaves

What to Do

1.Cover transplants with row cover (Agribon AG-19 or equivalent) immediately at planting — flea beetles find plants fast
2.For cabbage looper, hand-pick caterpillars in the morning and apply Bt (Bacillus thuringiensis) at dusk when larvae are actively feeding
3.NC State Extension notes that stressed plants draw heavier insect pressure — keep moisture consistent so Haku doesn't go drought-stressed between waterings

Outer leaves yellow and wilt; pulling the plant reveals swollen, distorted roots that smell faintly rotten

Likely Causes

Clubroot (Plasmodiophora brassicae) — a soil-borne pathogen that persists for 20+ years and moves on contaminated tools or transplants
Fusarium wilt (Fusarium oxysporum) — a separate fungal issue that also causes yellowing and collapse, but leaves roots discolored rather than galled

What to Do

1.No cure once a plant is infected — remove the whole plant, roots and all, and bag it for the trash, not the compost
2.Don't put any Brassica family crop (cabbage, broccoli, kale, turnips) back in that bed for at least 4 years; NC State Extension's disease chapter notes that Plasmodiophora brassicae doesn't disappear quickly with short rotations
3.If clubroot is confirmed, raise soil pH toward 7.2 with agricultural lime — the pathogen is far less active above pH 7.0

Frequently Asked Questions

How long does Haku cabbage take to harvest?▼

Haku cabbage reaches maturity in approximately 55 days from transplant. This relatively quick maturation makes it ideal for gardeners looking for a faster harvest. Timing from seed to harvest will be longer, typically 70-80 days, depending on starting conditions and growing season variables.

Is Haku cabbage good for beginner gardeners?▼

Yes, Haku is an excellent choice for beginners. It's rated as an easy-to-grow variety with exceptional adaptability across different regions. Its heat and tipburn tolerance mean it performs well even when conditions aren't perfect, making it forgiving for new gardeners learning to manage their crops.

Can you grow Haku cabbage in containers?▼

While Haku cabbage can technically be grown in containers, it prefers in-ground cultivation given its head size (11" tall, 5.5-6 lbs). You would need a very large container (at least 20+ gallons) with excellent drainage. In-ground or raised bed planting is recommended for best results and easier management.

What does Haku cabbage taste like?▼

Haku cabbage offers a mild, tender flavor typical of Chinese-type cabbages. It's less peppery than storage cabbages and works well raw in slaws or cooked in stir-fries. The leaves are crisp and slightly sweet, making it versatile for both Asian and Western cuisine applications.

Is Haku cabbage heat tolerant?▼

Yes, Haku is specifically bred for heat tolerance and is noted as the most heat-tolerant variety in its class. It performs exceptionally well in warm climates, making it ideal for Southern gardens, Arizona, California, and the Eastern Seaboard where summer heat can stress other cabbage varieties.

When should I plant Haku cabbage?▼

For spring crops, start seeds indoors 4-6 weeks before the last frost and transplant after danger of frost passes. For fall crops (often more successful), sow directly or transplant in mid to late summer for harvest before the first frost. Haku's heat tolerance makes fall planting particularly successful in many regions.