Cucurbita maxima | 45-50 days from flowering (pollination)

Hearty, tender and bursting with natural sweetness, kabocha squash is a core element of Washoku. Zuccuri is a specific variety of kabocha which is likened to a chestnut (kuri) in its sweetness and texture. This versatile squash is packed with flavor and nutrition, from its vibrant orange interior to its edible dark green skin. Its soft consistency first crumbles and then melts in the mouth, a unique characteristic that comes from its starch content. 

Kabocha squashes like Zuccuri are a winter staple in Japan and a reliable source of vitamins when vitamin- and carotene-rich vegetables are scarce, as they can be stored for upwards of three months in a cool, dry place. Traditionally enjoyed on winter solstice in Japan, Zuccuri is often prepared in a sweet soup with adzuki beans in the wintertime, as it is believed to help boost the immune system and prevent colds.

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Cooking with Zuccuri

Enjoy Zuccuri simmered, sautéed, dipped in tempura batter and fried, or roasted for a saccharine, melt-in-your-mouth sensory experience. This sweet kabocha squash pairs well with warming spices like nutmeg, clove and sage, as well as pears, cilantro, spinach, and parsley.

Zuccuri holds its form well when cooked and can be added in cubes to soups, stews, curries and casseroles. For a very simple and fast preparation, try microwaving one-fourth of the Zuccuri (500g approx.) for six minutes.

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Growing Details


  • Direct seeding: sow 1–2 seeds every 8”, 1/2” deep when daytime temps reach 72° F.
  • Once true leaves emerge, thin to one plant per 18” spacing with 40” between rows.
  • Transplanting: Sow 1-2 seeds per cell into a 50- or 72-cell tray.
  • Sow seeds 1/2" deep and cover gently. Avoid pressing firmly as compaction can cause difficulty transplanting.
  • Once established, thin to one plant per cell. 
  • Over-watering can create a crust-like soil layer, preventing germination. Maintain soil moisture through germination. 


  • Check for readiness 21-24 days after germination by gently pulling on the base of the stem to see if the soil block stays together. Avoid overgrown seedlings as this will impact future plant growth.
  • Transplant to 18" spacing, with 40” between rows.  


  • Cultivate planting beds to prevent weed competition and avoid sitting water, which can harbor mildew.
  • Use of light row cover can maintain heat and prevent pest damage. Remove at flowering.
  • Remove early fruits if leaves are less than 12” in diameter.


  • Harvest when stems turn from green to woody by cutting the fruit stem away from the vine (do not rip fruit stem).
  • Or harvest when the sum of daily average temperature from flowering (pollination) reaches 3400F. (If 68F everyday, it takes 50 days.)
  • Cure for peak ripeness by leaving fruits in a protected area away from sunlight. Curing time varies by variety:
  • 817: cure for 14 days.
  • 819: cure for 30 days. 

Curing & Storage

Use this chart to understand the curing and storage times of each variety.

Zuccuri 7 should be cured for 14 days in the shade, and then is best when eaten within two months.

Zuccuri 9 should be cured for 30 days, and can store up to 4 months.

  • Grow your own

    Seeds are available for purchase from packets to bulk, with multiple maturities.

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  • Growing details

    For more growing details, vist the blog posts on germination, growing and harvesting Zuccuri.

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  • Cook with Zuccuri

    For cooking information including recipes from the Culinary Institute of America, visit the blog.

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