The ripening speed of watermelon is affected by temperature, light intensity and time. It is best to indicate the date of pollination. When it is expected to mature, take a sample of melon, cut open the fruit, measure its sugar and taste it, and collect it in batches according to the mark after confirming its maturity.

Mature varieties need 90-90 days from sowing to harvesting, melons mature quickly, and it takes 25-30 days from female flower to maturity, which is suitable for close planting. Excellent varieties include Xin Jing, Zhengza, Zaohua and other small melon varieties. ?

For medium-mature varieties, it takes 90- 100 days from sowing to harvesting in the north, melon matures later, and it takes 30-40 days for female flowers to bloom and mature, with large plant type and strong growth. This kind of melon is big and thick, and it is resistant to transportation and storage, such as Xinong R.

Late-maturing varieties, such as Kouyuu No.2, need 100- 120 days from sowing to harvesting in the north, with less soft culture, big melon and good storage resistance.

Extended data:

Watermelon annual vine; Stems and branches are stout with obvious edges. Tendrils stout, pubescent, petiole thick and densely pilose; The leaf blade is papery, triangular, oval in outline, white and green in color, with short bristles on both sides and heart-shaped at the base of the leaf blade. Monoecious. Both male and female flowers are solitary in leaf axils.

Male pedicels 3-4 cm long, densely yellow-brown villous; Calyx tube wide bell-shaped; Corolla yellowish; Stamens nearly free, filaments short, anthers folded. Female flowers: calyx and corolla are the same as male flowers; Ovary ovoid, stigma kidney-shaped. The fruit is large, nearly spherical or oval, fleshy, juicy, with smooth skin and various colors and patterns.

Seeds are mostly oval, black and red, with smooth sides, obtuse base, usually slightly arched edges, and in summer.

There are many cultivated varieties in China, with different exocarp, pulp and seed shapes, among which Xinjiang, Lanzhou, Gansu, Dezhou, Shandong and Dongtai, Jiangsu are the most famous. Its original species may come from Africa, and it has been widely cultivated in tropical to temperate regions of the world for a long time, and was introduced to China in the Jin and Yuan Dynasties.

References:

Baidu encyclopedia-watermelon