Squash 'Delica F1'

Squash ‘Delica F1’ is an extremely popular variety of Japanese Kabocha type, winter squash. The plants produce an unusual shaped, flattened globe shaped, dark green striped fruit which covers a bright orange, creamy interior.
Adaptable to many growing and soil conditions, the plants performs best in moderate temperatures, consistently producing 1.7 to 1.9kg (3.75 to 4lb) high quality, flat, globe-shaped fruit with dark green rinds. Growing well in cool areas, the fruits also store well.

Introduced in Japan in 1964, it is a little more prolific than its next relatives, it matures in 95 to 105 days producing fruits that are rounded but flattened. The flesh is of excellent quality. Dark yellow to orange; thick, firm and fine-grained. It is sweet with a delicate taste of chestnut.
This winter squash is one of the extremely popular Ebisu type varieties grown in Japan. 'Ebisu' is the name of one of the gods of luck, the patron saint of fishermen and women and business people.

Kabocha has an exceptional sweet flavour, even sweeter than butternut squash. It is similar in texture and flavour to a pumpkin and sweet potato combined. It can be used in any recipe calling for butternut or acorn squash, they are the perfect size for 4 to 6 meals and can be prepared as main courses, salads, side dishes or desserts.
One of the advantages of using these varieties, besides their sweet nutty flavour, is their texture, they are known for their drier flesh. They hold their shape in stews and curries, and if used raw and grated into a winter salad, they’ll add a sweet crunch and burst of orange colour.
The delicious dense firm flesh has a superb sweet flavour which is beautiful cut into slices and steamed gently until tender. With a weight at around 1.8kg, use for roasting with the joint, soups and pumpkin pie.
The thin, hard rind surrounds orange flesh that is sweet, stringless and highly desirable - so sweet it can actually be used like a sweet potato. It's perfect mashed, pureed, steamed, or as a sweet potato replacement in most recipes. The squash are perfect for filling and roasting, turning them into beautiful bowls with grains, sage and more veggies is a full sensory experience.

Prepare the Site:
Choose a sunny, sheltered spot with moisture retentive, humus rich soil. Improve the soil by digging in some well-rotted manure or compost. The simplest way is to dig a hole 30cm (12in) deep and 45cm (18in) across and fill it with well rotted compost or manure. Cover with a 15 to 20cm (6-8in) layer of soil to make a raised mound that will provide drainage along with a rich source of nutrients. Left to their own devices the plants will trail for several feet in all directions. Ideally each plant needs 120cm square (4ft square) in order to spread and avoid competing with nearby plants. (Alternatively you can grow them in large containers).

Sowing: Sow indoors in pots April to June or sow direct from mid May to the end of June.
A minimum temperature of 10°C (50°F) will be needed for germination, depending on the time of year, this can be supplied in the greenhouse, glazed porch, or cold frame.
If grown entirely in a heated greenhouse seed can be sown in situ in late winter, or early spring for transplanting to a cloche or cold frame. If you do not have any glass, then delay sowing until late spring to avoid damage from heavy frost.

Sowing indoors:
Fill 7.5cm (3in) pots with compost and firm gently. Sow seed on its side, not flat to ensure reliable germination. Sow 12mm (½in) deep and cover. (You may choose to sow two seeds per pot, and remove the weaker seedling later; the strongest plants are kept.) Label, water and put in a propagator or on a windowsill.
Germination should take place 10 to 14 days later. If temperatures are higher it may only be 4 to 6 days. After germination the young plants will grow very quickly and will need repotting almost at once. When roots begin to show through the bottom of the pot, transplant to a 12.5cm (5in) container. Keep barely moist to prevent stems from rotting and protect from strong sunlight with a sheet of newspaper.
Hardened off before planting outside, around late May/early June and all danger of frost has passed. Plant out with 120cm (48in) between plants, providing good air circulation to avoid mildew. Protect seedlings from slugs.

Sowing directly outdoors:
Early sowing outdoors is rarely of much benefit as the seeds may not germinate if the soil is too cold, or cold temperatures may damage young plants. Four weeks before the last frost is expected is about right.
Sow two or three seeds 2.5cm (1in) deep on their edges under cloches or glass jars with 45 to 60cm (18 to 24in) between plants. Remove the weaker seedlings later.

Cultivation:
Hoe gently to keep the weeds down and do not let the plants dry out. Plenty of water is essential, especially when the plants are in flower and when the fruits have started to swell. Avoid splashing water on the stems of the young plants. Apply a mulch of about 12mm (1in) deep of grass cuttings or compost after watering. This helps conserve soil moisture and keeps the weeds down.
If you dig in plenty of manure before planting, additional feeding is unnecessary on heavy, fertile soil. On sandy or light soil, regular liquid feed will help boost production.
Plants under glass should be hand pollinated. The female flowers are distinguished by the swelling below the bloom. Male flowers have a prominent central core, bearing yellow pollen. The male flower is first to appear and the female flowers will follow. To hand pollinate, remove the petals from a male flower; push the core into the centre of the female flower. For a high success rate, use a different male for each female flower.

Harvesting: 95 to 105 days (45 to 50 days after flowering)
Unlike summer squashes, such as courgettes and marrows, it pays to let winter squashes ripen thoroughly. If you harvest the fruits regularly you will get a heavier crop over a longer season.
You will know that your plants are ready after the rind of the vegetable has hardened and the stem is two inches long. If you harvest it before it is fully mature it will lose its sweet flavour. Harvest before the temperature falls. Use a sharp knife or secateurs to sever the fruit from the plant leaving a short stem, do not pull them off. Harvest all fruits before heavy frost, and they can be stored indoors at 10°C for several months.

Ripening:
Just like pears, kabocha squash ripen after harvest and they taste best when they are fully but not overly ripe. They need to ripen for one or more months after harvest for best culinary quality. At harvest, they still have high starch and low sugar contents. During ripening, starch is converted to sugars, which improves the consistency of the squash and increases sweetness.
When kabocha is just harvested, it is still growing. Therefore, unlike other vegetables and fruits, freshness is not as important. The fruits should be fully matured in order to become flavourful, by first ripening the kabocha in a warm place 25°C (77°F) for 13 days to convert some of the starch to sugar. Then the kabocha is transferred to a cool place, 10°C (50°F) and stored for about a month in order to increase carbohydrate content. In this way the just-harvested, dry kabocha is transformed into a smooth, sweet kabocha. Fully ripened, succulent kabocha will have reddish-yellow flesh, a hard skin, and a dry, corky stem. It reaches the peak of ripeness about 1 to 3 months after it is harvested.

Storing:
Before storing, cure the fruit. Curing is best accomplished by allowing them to remain in the sunshine for about ten days. It is the sunlight that cures or hardens the skin. If there is a chance of freezing weather, protect in a storage building and return to the sunlight the following day.
If you cure the fruit and store them properly, they will last well into the winter. The storage area should be dark, about 10°C (50°F), and rather dry (less than 65% humidity).

Origin:
The Kabocha is a type of winter squash, a Japanese variety of the species Cucurbita maxima. Portuguese sailors introduced kabocha to Japan in 1541, bringing it with them from Cambodia.
Pumpkins were eaten in Japan as a subsistence food during World War II, so kabochas were not the first choice of consumers in the years immediately following the war. However, when Takii Seed Company introduced the dark green ‘Delica’ (aka ‘Ebisu’), which was launched in 1964. this F1 hybrid kabocha became extremely popular.
During the 1970s, more U.S. seed companies gradually started selling kabochas, spurred by an interest in healthy eating and macrobiotic cooking. For example, Johnny’s Selected Seeds listed ‘Blue Kuri’ in 1974 and ‘Uchiki Kuri’ in 1976. By the late 1980s, kabochas became increasingly common in American seed catalogues, along with many other specialty and international vegetables.
We do not know which Cucurbita maxima varieties were used in Japanese kabocha breeding. There were many other small hubbard and turban varieties available with dry flesh in the late 19th and early 20th centuries. Japanese commercial kabocha varieties do not typically have a protruding 'turban' or 'button' on the blossom end; however, there are local heirloom varieties that have this characteristic in some regions of Japan.

Nomenclature:
Portuguese sailors introduced kabocha to Japan in 1541, bringing it with them from Cambodia. The Portuguese name for the squash, Camboja abóbora, was shortened by the Japanese to kabocha. Also, the Portuguese origin is the word cabaça for gourd. Kabocha meaning in Kanji is literally, 'southern melon', and occasionally 'Nanking melon'. In China, this term is applied to many types of squashes with harder skin and beefier flesh, including pumpkins.
It is also called kabocha squash or Japanese pumpkin in North America. In Japan the name kabocha may refer to either this squash, to the Western pumpkin, or indeed to other squashes.
Many of the kabocha in the market are Kuri kabocha, a type created from Seiyo Kabocha (The Buttercup squash).
Introduced in Japan in 1964, Squash 'Delica F1' is one of the extremely popular Ebisu type varieties grown in Japan. 'Ebisu' is the name of one of the gods of luck, the patron saint of fishermen and women and business people.