How to Grow Japanese Cucumber

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Japanese Cucumber

Cucumis sativus var. japonica

vegetable

Japanese cucumbers are slender, thin-skinned varieties that typically grow 8-12 inches long with fewer seeds and a more delicate texture than standard slicing cucumbers. They have a crisp, mild flavor and tender skin that requires no peeling. Originally cultivated in Japan, they are now widely grown in home and commercial gardens for fresh eating and light pickling.

Looking for a specific variety?

Suyo Long Japanese White Orient Express Armenian Kyoto Long Tatsuta

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Example Japanese Cucumber timeline · Pittsburgh, PA (Zone 6b)

Plant Japanese Cucumber
Around Apr 17

Near Pittsburgh's average last spring frost.
Tend & protect
Late spring–summer

Watering, feeding, and pest-watch reminders.
Harvest Japanese Cucumber
Around Jun 6

≈ 50 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Japanese Cucumber dates for your own zip code.

Growing Conditions

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Sun: Full sun, 6-8 hours daily minimum; 8+ hours ideal for best productivity

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Water: Consistent moisture, 1-2 inches per week; keep soil evenly moist but not waterlogged. Water at soil level in morning to reduce disease. More frequent watering in hot weather and during fruiting.

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Spacing: 12-18 inches apart in rows, or 24-36 inches between hills if trellising; rows 3-4 feet apart inches

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Days to maturity: 50-70 days from transplant, 60-80 days from direct seeding

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Planting depth: 0.75-1 inch deep; plant seeds directly or use 3-4 week old transplants

Soil

Type: Rich, well-draining loamy soil with good organic matter

pH: 6.0-7.0

Amendments:

Compost aged manure peat moss or coco coir perlite for drainage

Growing Zones

Find your zone →

Thrives in zones 4-10; warm-season annual planted after last frost

3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a

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Growth Stages

Seedling

2-3 weeks

Two cotyledons emerge, followed by true leaves; seedlings are tender with thin stems and small leaves

Keep soil consistently moist but not soggy. Provide bright light (12-14 hours). Harden off transplants before planting outdoors.

Vegetative Growth

2-3 weeks

Rapid vine elongation with multiple leaf nodes; vines grow 6-12 inches per week in warm conditions. Tendrils develop for climbing.

Trellis or stake for vertical growth to save space and improve air circulation. Water deeply and regularly. Begin fertilizing with balanced or slightly higher nitrogen formula every 2-3 weeks.

Flowering

1-2 weeks

Small yellow flowers appear at leaf nodes; male flowers come first, followed by female flowers (identifiable by small fruit behind the bloom)

Maintain consistent watering and warmth (70-85°F ideal). Switch to lower nitrogen fertilizer to encourage fruiting. Ensure adequate pollination by bees or hand-pollinate if needed.

Fruiting & Growth

3-5 weeks

Slender, dark green fruits develop rapidly and elongate. Multiple cucumbers may grow simultaneously along the vine.

Pick fruits at 6-8 inches long for best quality and continued production. Water deeply and frequently (daily in heat). Provide consistent fertilizing (every 7-10 days). Remove any diseased leaves.

Peak Production & Harvest

4-6 weeks

Plant reaches peak productivity with multiple harvestable fruits daily or every other day. Older leaves may yellow as plant channels energy to fruit

Harvest every 2-3 days to encourage continuous production. Keep vines clear of dead foliage. Continue regular watering and feeding. Production slows as temperatures drop below 60°F or exceed 90°F.

Companion Planting

Plan your garden →

Plant with:

Basil Dill Nasturtium Radish Corn Beans Peas Marigold Oregano

Avoid planting near:

Fennel Rue Sage Aromatic herbs in general Potatoes Kohlrabi Late brassicas

Common Pests

Row covers until flowering; yellow sticky traps; neem oil or insecticidal soap; hand-picking; insect exclusion netting
Ensure good air circulation; spray with sulfur or potassium bicarbonate; remove infected leaves; avoid overhead watering
Improve air circulation; apply copper fungicide; water at soil level; remove infected foliage promptly
Increase humidity; spray leaves with water; use miticides if severe; neem oil; remove heavily infested leaves
Strong water spray; insecticidal soap; neem oil; ladybugs and lacewings; reflective mulches
Row covers in early season; plant succession crops; inject Bacillus thuringiensis into stems; remove and destroy affected vines

Uses

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Fresh eating and salads

Culinary

Japanese cucumbers have thin, tender, edible skin requiring no peeling and minimal seeds, making them ideal for fresh slicing, salads, and raw consumption. Their mild, crisp flavor and delicate texture distinguish them from thicker-skinned varieties. [source]

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Light pickling and fermentation

Culinary

The slender shape and tender skin make Japanese cucumbers excellent for quick pickles, refrigerator pickles, and Japanese-style tsukemono (pickled vegetables). Their smaller seed cavity also means less brine absorption and faster pickling. [source]

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Skincare and cosmetics

Household

Cucumber slices and juice have been traditionally used for soothing skin, reducing puffiness, and providing hydration. The mild nature and thin skin of Japanese varieties make them gentle for direct skin application. [source]

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Japanese cuisine applications

Culinary

Japanese cucumbers are integral to dishes like sunomono (vinegared salad), sushi rolls, miso soup accompaniments, and tempura. Their delicate texture holds up well to traditional Japanese preparation methods. [source]

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Hydration and digestive support

Medicinal

Cucumbers are approximately 95% water, providing hydration and containing fiber for digestive health. They also contain lignans and flavonoids with anti-inflammatory properties. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Harvest when fruits are 6-8 inches long, slender, and deep green with a glossy appearance. Pick every 2-3 days to encourage continuous production and prevent fruit from becoming overripe and seedy. Grasp the fruit and twist gently or use pruning shears. Handle carefully to avoid bruising. Harvest in morning for crispest texture. Japanese cucumbers deteriorate quickly if left on vine too long.

Fun Facts

🌱 Japanese cucumbers can produce 15-20+ fruits per plant over a season with proper care, making them exceptionally prolific compared to standard slicing varieties.
🌱 The variety is sometimes called 'greenhouse cucumber' or 'hothouse cucumber' because it was originally bred for protected cultivation in Japanese greenhouses to achieve its characteristic thin skin and uniform shape.
🌱 Unlike most cucumber varieties, some Japanese types are parthenocarpic, meaning they can set fruit without pollination, though pollination still improves yields.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Full Sun Pollination Transplant Trellis True Leaves

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