When do grapes ripen?
In the cycle of fruits throughout the seasons, grapes attract countless gourmands with their unique growth cycle and rich variety. Knowing the ripening time of grapes not only concerns the best tasting experience but also helps growers master the golden harvest period. This article will comprehensively analyze the growth code of this berry from three dimensions: regional differences, variety characteristics, and artificial intervention.
Regional characteristics of grape ripening season
Difference in ripening time between southern and northern growing areas
Thanks to abundant accumulated temperature, varieties like巨峰 (Jumbo Peak) can be marketed in late June in the southern region. Fresh grapes in the Yangtze River Valley mostly ripen in July-August, while in the northwestern regions like (X-J) Turpan, varieties such as 无核白 (Seedless White) need to accumulate sugars until late August due to the large diurnal temperature difference.
Special landform microclimate
Grapes in the valley area ripen 5-7 days earlier than those in the plain, and the mountain planting forms a stepped maturation sequence due to the temperature gradient changes. The dry-hot valley area of Yuanmou in Yunnan can even achieve a special cultivation mode with two harvests per year.
Difference in ripening cycles of grape varieties
Characteristics of early-ripening varieties
Summer Black grapes, with a growth period of 110 days, become the earliest fresh food variety on the market. European varieties like 维多利亚 (Victoria) can ripen as early as mid-May under facility cultivation.
Advantages of late-ripening varieties
Wine grape varieties like 赤霞珠 (Cabernet Sauvignon) require a growth period of over 160 days, and delayed harvesting can increase the tannin content. (X-J)穆纳格 (Munage) grapes can extend the harvest period to late October through on-tree preservation technology.
Impact of artificial intervention on the ripening period
Facility cultivation technology
Modern greenhouses can achieve off-season production through temperature and light control, and with the help of supplementary lighting and ground heating systems, Jumbo Peak grapes can ripen 45 days earlier. Attention should be paid to maintaining the diurnal temperature difference in reverse-season cultivation to ensure fruit quality.
Plant growth regulators
Reasonable use of external hormones like gibberellic acid can adjust the rhythm of fruit development, but strict adherence to the safety interval is required. The combination of biostimulants and precision irrigation can synchronize the maturation process.
From flowering to sugar conversion, the ripening of grapes is a perfect concerto between natural laws and agricultural technology. Mastering the variety characteristics and regional features, combined with modern cultivation techniques, can extend the fresh grape (G-Y) period and improve the quality of wine grapes. Consumers can judge the real maturity by features such as the completeness of the fruit powder and the degree of woodiness of the fruit stem.