Key Technical Points for Early-Maturing, High-Yield Winter Melon Cultivation

WINTER MELON (fatmelon; white fuzzy vegetable). Botanical classification: Angiosperms, Dicotyledoneae, Cucurbitales, Cucurbitaceae, Benincasa Savi, an annual herbaceous plant. The fruit is pillow-shaped, hence it is also called pillow melon, and it is produced in summer. Why is a melon produced in summer given the name winter melon? This is because when the fruit ripens, its surface carries a layer of white powdery substance, just like the white frost formed in winter; for this same reason, winter melon is also called white melon.

Botanical morphology of winter melon: an annual trailing or trellis-grown herb; the stem is covered with yellowish-brown bristles and long soft hairs, and has angular grooves. The petiole is stout, 5-20 cm long, covered with yellowish-brown bristles and long soft hairs; the leaf blade is kidney-shaped and nearly round, 15-30 cm wide, with 5-7 shallow lobes or sometimes medium lobes, the lobes broadly triangular or ovate, acute at the apex, with small teeth along the margin, deeply cordate at the base, the sinus open, nearly round, 2.5-3.5 cm deep and wide, the upper surface dark green, slightly rough, with sparse soft hairs that gradually fall off with age and become nearly glabrous; the lower surface rough, grayish-white, with coarse bristles, the veins slightly raised on the lower surface of the leaf and densely hairy. Tendrils 2-3 branched, covered with coarse bristles and long soft hairs. Monoecious; flowers solitary.

The male flower pedicel is 5-15 cm long, densely covered with yellowish-brown short bristles and long soft hairs, often with a bract at the base of the pedicel, the bract ovate or broadly oblong, 6-10 mm long, acute at the apex, with short soft hairs; the calyx tube broadly campanulate, 12-15 mm wide, densely covered with bristle-like long soft hairs, the lobes lanceolate, 8-12 mm long, serrate, reflexed; the corolla yellow, rotate, the lobes broadly obovate, 3-6 cm long, 2.5-3.5 cm wide, sparsely soft-hairy on both surfaces, obtuse-rounded at the apex, with 5 veins; stamens 3, free, the filaments 2-3 mm long, enlarged at the base, hairy, the anthers 5 mm long, 7-10 mm wide, the thecae curved in 3 folds; the female flower pedicel less than 5 cm long, densely covered with yellowish-brown bristles and long soft hairs; the ovary ovate or cylindrical, densely covered with yellowish-brown downy bristles, 2-4 cm long; the style 2-3 mm long, the stigmas 3, 12-15 mm long, 2-lobed. The fruit is long-cylindrical or nearly spherical, large, with bristles and white bloom, 25-60 cm long, 10-25 cm in diameter. The seeds are ovate, white or pale yellow, flattened, margined, 10-11 mm long, 5-7 mm wide, 2 mm thick.

How can winter melon cultivation achieve early maturity and high yield?

Variety selection

Choose early-maturing, high-quality small green-skinned winter melon varieties. Generally sow from late January to February; before sowing, soak the seeds in warm water and adjust the moisture of the seedling bed properly. Sow 100-150 grams per square meter, and after sowing cover the ground with a plastic film arched shed to help retain heat. Before emergence, keep the humidity inside the seedling bed at 35°C during the day, and no lower than 15°C at night. Thin the seedlings when the cotyledons are flat and spread; because winter melon seeds have a thick coat and emerge at different times, thin each batch as it emerges, with a seedling spacing of 8 cm as appropriate. When thinning, keep the bed soil temperature at 25°C-30°C during the day and no lower than 15°C at night. When the seedlings reach the 3-leaf 1-heart stage, cut and lift the seedlings for temporary crowding, with a seedling spacing of about 15 cm. Newly planted seedlings should be kept closed for warmth; after they are established, begin ventilation, increasing the ventilation volume from small to large. After the seedlings grow normally in late March, uncover the film during the day to harden the seedlings so they become vigorous, and at the same time manage the moisture of the seedling bed well, keeping the bed soil suitably dry and moist. Water at noon on a sunny day, and ventilate appropriately after watering to reduce air humidity. Also use pesticides such as dimethoate to control aphids and other pests and diseases.

Site selection and land preparation

Choose a plot with high, well-drained terrain. After the previous crop of melons is harvested, plow and sun-bleach the soil promptly, then prepare the land and make beds. The bed width including the ditch is 3.7 m; together with land preparation, apply 3000 kg of decomposed organic fertilizer and 75 kg of compound fertilizer per mu, applied in a band on one side where the winter melons will be planted. Make the bed surface sloped, planting winter melons on the higher side and tomatoes on the lower side; this can thicken the plow layer at the winter melon roots, benefiting vine growth and fruit setting in the middle and late stages. Generally plant around Qingming, with 1 row per bed, a plant spacing of 60 cm, and about 500 plants per mu.

Transplanting management

For newly transplanted winter melons, focus on keeping them warm; in cold weather, a small plastic film arched shed can be set up and kept closed for 7-8 days to promote early recovery of the seedlings. As growth resumes, gradually carry out ventilation and air exchange, first at the two ends, then in the middle, gradually increasing the ventilation volume. As the temperature rises and the seedlings grow larger, the arched shed can be removed. After transplanting, water promptly to settle the roots. Before female flowers appear, apply dilute manure water 1-2 times according to plant growth, to promote early and steady growth. After female flowers appear, apply manure fertilizer around the roots to promote vine growth and fruit setting. Thereafter, topdress about once every 7 days according to growth and fruit set. During the harvest stage, appropriately increase the amount and concentration of topdressing so the plants grow vigorously without early decline. In drought, irrigate the ditch water to meet the winter melon's water needs. When the vines begin to trail on the ground, earth up the soil to increase the roots' capacity for absorption. When the vines are 70-80 cm long, begin guiding the vines onto the trellis on a sunny day, and thereafter regularly train and arrange the vines so they are evenly distributed. Winter melon is an insect-pollinated crop, so hand pollination is needed; on a sunny morning before the dew dries, select fully open male flowers and gently dab the stamens onto the stigmas of the female flowers; 1 male flower can pollinate 2-3 female flowers, which can markedly increase the early fruit-setting rate. Do not pollinate plants with poor vigor or female flowers within the first 10 leaves, to avoid setting fruit too early and affecting plant vigor.

Pest and disease control

Clear the ditches in the melon field frequently to prevent waterlogging and reduce disease. Anthracnose, gummy stem blight, phytophthora blight, aphids, red spider mites, and so on can be controlled with conventional pesticides. In high temperature and strong light, cover the winter melons with grass or a shade net to avoid sunscald. Harvest the first melon around early June, and thereafter harvest promptly according to market conditions. When picking, avoid trampling the vines, so the vines always remain in good growth without early decline.