White Dew Farming

During White Dew, Northeast China enters the full “三秋” autumn-harvest rush. Maize, rice, and soybeans are harvested simultaneously, while early-frost risk reaches its annual peak, making this one of the busiest and most critical periods of the agricultural year.
Full maize harvest. Spring maize across Northeast China enters full harvest during White Dew. The husks turn white, kernels harden, the milk line disappears, and the black layer forms, indicating physiological maturity. Farmers seize clear weather for harvest while combines operate day and night, completing maize harvest, threshing, and stalk shredding in a single operation. After harvest, grain is promptly dried until moisture falls below 14% before storage, or mechanically dried. The maize harvest window generally lasts only 2–3 weeks, so weather forecasts require close attention. If rain is expected, harvesting should be completed before rainfall or rain-protection measures such as tarpaulin covering should be prepared. Harvesting too early leaves kernels insufficiently filled and thousand-kernel weight low, while harvesting too late increases the risk of bird and rodent damage or mold after rainfall. White Dew is the most concentrated period for maize harvest in Northeast China.
Full rice harvest. Rice across Northeast China enters full harvest during White Dew. Panicles turn yellow, grains become full and hard, and the crop reaches physiological maturity. Farmers seize clear weather for harvest as rice combines operate in the paddies. After harvest, grain is promptly dried until moisture falls below 14% before storage, or mechanically dried. The rice harvest window generally lasts only 1–2 weeks, requiring close attention to weather forecasts. If rain is expected, harvesting needs to be completed before it arrives, as rainfall can cause rice grain to germinate or develop mold. Harvesting too early leaves grains insufficiently filled, reducing thousand-kernel weight and increasing unfilled grains, while harvesting too late can cause shattering or germination after rain.
Full soybean harvest. Soybeans across Northeast China enter full harvest during White Dew. Leaves have all fallen, pods turn yellow, and seeds become full and hard, reaching physiological maturity. Farmers seize clear weather for harvest as soybean combines operate in the fields. After harvest, soybeans are promptly dried until moisture falls below 13% before storage. The soybean harvest window generally lasts only 1–2 weeks. Harvesting too early leaves seeds insufficiently filled, while harvesting too late makes pods prone to shattering and seed loss.
Peak early-frost risk. White Dew is the period of highest early-frost risk in Northeast China. Northern Heilongjiang and northeastern Inner Mongolia may experience early frost from early to mid-September. Early frost is the greatest threat to the autumn harvest in Northeast China: a single frost can damage immature or unharvested maize, rice, and soybeans, causing major yield losses or even total crop failure. Preventive measures include rapid harvesting, prioritizing mature crops, early-maturing cultivars, higher-elevation fields, and frost-prone plots before frost arrives; pre-frost irrigation, applying 5–10 centimeters of water before forecast frost to conserve heat, using water’s high specific heat capacity to delay cooling and raise surface temperature by 2–3°C, which is the most effective frost-prevention measure during White Dew; and application of cold-resistant agents, including advance spraying of cold-protection products or monopotassium phosphate to improve cold resistance.
Winter forage reserves in pastoral areas. Herders in eastern Inner Mongolia begin large-scale cutting, drying, baling, and storage of winter forage in preparation for the safe overwintering of livestock.

During White Dew, Northwest China enters a critical stage of autumn management. Cotton reaches peak harvest, orchard harvesting continues, and winter-wheat sowing gradually begins.
Peak cotton harvest. Cotton across Xinjiang enters peak harvest during White Dew, with large numbers of bolls opening and lint becoming exposed, reaching harvest standards. Farmers seize clear weather for picking. Manual harvesting remains predominant in Xinjiang cotton areas, with strict picking standards: only fully opened white cotton is collected, while incompletely opened green cotton and contaminated cotton are left unpicked, and care is taken to prevent foreign matter from entering during harvest. After picking, cotton is promptly dried, graded, baled, and stored or sold. The cotton harvest generally lasts 1–2 months, from late August to late October, with the period from White Dew to Autumn Equinox being the most concentrated stage. Weather forecasts require close attention; if rain is expected, cotton should be harvested before rainfall because wetting reduces fiber quality and can cause yellowing and mold.
Continued orchard harvest. Harvesting of apples, fragrant pears, grapes, and other fruits continues across southern Xinjiang. Fragrant-pear harvest enters its final stage. The harvest period generally runs from mid- to late August through early September, followed by prompt precooling, grading, packing, cold storage, or sale. Fragrant pears are among Xinjiang’s most distinctive fruits and are subject to very high quality standards. Grape harvesting enters its peak, with table-grape harvesting continuing and wine grapes harvested intensively in September once sugar and acidity reach winemaking standards, bringing wineries into the busiest crush season of the year. Harvesting of early apple cultivars such as “嘎啦” and “美国八号” continues, while mid-season cultivars such as “红星” and “金冠” begin harvest. Growers need to pay attention to harvesting at the proper stage according to maturity. For apples, harvest standards include skin coloration ≥80%, firmness ≥8 kg/cm², and sugar content ≥13%. Postharvest management includes prompt precooling, grading, packing, cold storage or sale, followed by pruning and fertilization to restore tree vigor.
Winter-wheat sowing gradually begins. During White Dew, winter-wheat sowing gradually begins across Northwest China. In northern Xinjiang, winter wheat is sown in mid- to late September; the earlier sowing period takes advantage of autumn cooling and winter snow cover to ensure safe overwintering. In Gansu’s Hexi Corridor, winter wheat is sown from late September to early October. Farmers plow fields to a depth of 20–25 centimeters, apply sufficient basal fertilizer through farmyard manure plus compound fertilizer, carefully select seed from cold-resistant, drought-resistant, and disease-resistant cultivars, and sow at the proper time to a depth of 3–5 centimeters, followed by soil firming to conserve moisture. The quality of winter-wheat sowing directly affects overwinter survival and yield the following year.
Specialty crops. Potato harvesting around Dingxi, Gansu, enters its final stage. Goji harvesting in Ningxia enters its final stage. Processing-tomato harvesting in Xinjiang also enters its final stage.

During White Dew, North China enters the busiest stage of the autumn harvest. Summer maize reaches peak maturity and harvest, cotton enters peak picking, and preparations for winter-wheat sowing gradually begin.
Peak summer-maize maturity and harvest. Summer maize across North China enters peak maturity and harvest during White Dew. The husks turn white, kernels harden, the milk line disappears, and the black layer forms, indicating physiological maturity. Farmers seize clear weather for harvest while combines operate day and night. After harvest, grain is promptly dried until moisture falls below 14% before storage. The summer-maize harvest window generally lasts only 1–2 weeks, requiring close attention to weather forecasts. If rain is expected, harvesting needs to be completed before it arrives. Harvesting too early leaves kernels insufficiently filled, while harvesting too late increases the risk of bird and rodent damage or mold after rainfall. The period from White Dew to Autumn Equinox is the most concentrated summer-maize harvest season in North China.
Spring-maize harvesting largely complete. By White Dew, spring-maize harvesting in North China is largely finished. Grain has been stored and stalk treatment is completed at the same time, either by returning stalks to the field or baling and removing them.
Peak cotton picking. Cotton across North China enters peak harvest during White Dew, with large numbers of bolls opening and lint becoming exposed. Farmers seize clear weather for picking, collecting only fully opened white cotton rather than green or contaminated cotton. After harvest, cotton is promptly dried, graded, baled, and sold. Cotton harvest continues through October, with the period from White Dew to Autumn Equinox being the most concentrated stage.
Preparations for winter-wheat sowing. During White Dew, preparations for winter-wheat sowing gradually begin across North China. Winter wheat is sown from late September through early October. The saying “白露早，寒露迟，秋分种麦正当时” describes Autumn Equinox as the appropriate sowing period for winter wheat in North China. Farmers begin purchasing seed, selecting cold-resistant, drought-resistant, and disease-resistant cultivars according to local climate and soil conditions; preparing fertilizer, mainly compound fertilizer as basal fertilizer at 20–25 kilograms per *mu*; servicing seed drills and adjusting sowing depth, row spacing, and seeding rate; and developing planting plans covering acreage, cultivar combinations, and sowing schedules.
Continued orchard harvest. Apple, pear, and other fruit harvesting continues across North China. Harvesting of early apple cultivars enters its final stage, while mid-season varieties such as “红星” and “金冠” reach peak harvest in September. Pear cultivars such as “鸭梨” and “皇冠梨” also enter peak harvest. Growers need to harvest at the proper stage, carry out postharvest management, and control fruit diseases during harvest.
Vegetable management. Open-field vegetables across North China enter peak harvest. Autumn-sown vegetables such as autumn Chinese cabbage and autumn radish enter critical growth stages and require stronger water and nutrient management and pest and disease control.

During White Dew, the middle and lower Yangtze enters a critical stage of autumn management. Middle-season rice enters full harvest, late rice enters heading and flowering, and preparations for autumn sowing gradually begin.
Full middle-season rice harvest. Middle-season rice across the Yangtze River basin enters full harvest during White Dew. Panicles turn yellow and grains become full and hard, reaching physiological maturity. Farmers seize clear weather for harvest while rice combines operate in the paddies. After harvest, grain is promptly dried until moisture falls below 14% before storage, or mechanically dried. The harvest window generally lasts only 1–2 weeks, so weather forecasts need to be followed closely. If rainfall associated with 华西秋雨 or a typhoon is expected, harvesting should be completed before the rain arrives.
Late-rice management during heading and flowering. Late rice across the Yangtze River basin enters heading and flowering during White Dew. Young panicles emerge, flowers open, and pollination takes place, making this a critical stage for determining seed-setting rate. Management centers on maintaining a shallow water layer of 3–5 centimeters without interruption; applying 穗肥, mainly potash, at 3–5 kilograms of potassium chloride per *mu* to promote flowering, seed set, and grain development; and monitoring weather closely. Persistent cloudy and rainy conditions associated with 华西秋雨 during heading and flowering can impair pollination and seed set, while temperatures of 32°C or above can render pollen inactive and increase the number of unfilled grains. Rice blast, sheath blight, planthoppers, and other pests and diseases enter critical treatment windows, and panicle-neck blast requires one application of tricyclazole before heading and another after full heading. Management during heading and flowering directly affects seed-setting rate and final yield.
Preparations for autumn sowing. During White Dew, preparations for autumn sowing gradually begin across the Yangtze River basin. Rapeseed is sown from late September through early October. The Yangtze River basin is China’s largest rapeseed-producing region, and rapeseed accounts for the largest share of autumn-sown acreage. Farmers begin purchasing rapeseed seed, choosing high-yielding, high-quality, disease-resistant cultivars such as the “中油” and “华油” series; preparing compound fertilizer as basal fertilizer at 20–25 kilograms per *mu*; and plowing and preparing fields promptly after the rice harvest.
Pest and disease control. Late-rice pests and diseases remain at high incidence during White Dew. Key targets include rice blast, particularly panicle-neck blast, treated with tricyclazole or isoprothiolane; sheath blight, treated with validamycin or difenoconazole + propiconazole; rice planthoppers, treated with imidacloprid or buprofezin; and stem borers, treated with dimehypo or Bt preparations. Farmers need to strengthen field inspections and intervene promptly when pests or diseases are detected.
Vegetables and aquaculture. Sowing and nursery raising of autumn vegetables across the Yangtze River basin—including autumn Chinese cabbage, autumn radish, autumn lettuce, and spinach—continue. In aquaculture, temperatures gradually fall while fish continue feeding actively, requiring stronger feeding management and water-quality management.

During White Dew, agricultural activity across Southwest China enters a critical stage of autumn management. Middle-season rice enters harvest, maize enters harvest, and preparations for rapeseed sowing gradually begin.
Middle-season rice harvest. Middle-season rice across Southwest China enters harvest during White Dew. Panicles turn yellow and grains become full, reaching physiological maturity. Farmers seize clear weather for harvesting, drying, and storage.
Maize harvest. Spring maize across Southwest China enters harvest during White Dew. The husks turn white and kernels harden, reaching physiological maturity. Farmers seize clear weather for harvesting, drying, and storage.
Preparations for rapeseed sowing. During White Dew, preparations for rapeseed sowing gradually begin across Southwest China. Rapeseed is sown from late September through early October, and farmers begin purchasing seed, preparing fertilizer, and plowing and preparing fields.
Orchard management. Citrus-growing regions across Southwest China enter fruit coloration. The fruit begins to change color and sugar starts to accumulate, making this a critical stage for determining citrus quality. Management centers on application of potash at 5–8 kilograms of potassium sulfate per *mu* to promote sugar accumulation and coloring; moderate water control to promote sugar accumulation without allowing excessive drought that would restrict fruit enlargement; and pest and disease control against citrus red mites, leaf miners, canker, anthracnose, and other problems entering critical treatment windows.
Potato harvest. Spring-potato harvesting continues across the major producing regions of Yunnan, Guizhou, and Sichuan. Middle- and late-maturing cultivars enter harvest and farmers seize clear weather for harvesting, drying, grading, and storage.

#### (1) Mainland South China
Late-rice management during heading and flowering. Late rice across South China enters heading and flowering during White Dew. Young panicles emerge and flowers open for pollination, making this the critical stage determining seed-setting rate. Management centers on maintaining a shallow water layer of 3–5 centimeters, applying 穗肥, mainly potash, at 3–5 kilograms of potassium chloride per *mu*, and controlling rice blast, sheath blight, planthoppers, and other pests and diseases entering critical treatment windows. Typhoon preparedness is also essential, as South China remains in an active typhoon period in September and strong winds and torrential rain can cause rice lodging and interfere with pollination.
Tropical-fruit management. Bananas in Guangdong, Guangxi, and Hainan move from fruit development toward pre-maturity and require stronger water and nutrient management through potash application to promote fruit development, together with typhoon preparedness by reinforcing banana plants and clearing drainage channels. Citrus enters fruit coloration, with fruits beginning to color and sugar accumulation beginning. Water and nutrient management needs to be strengthened through potash application to promote sugar accumulation and coloring, together with control of citrus red mites, leaf miners, canker, and other problems. Longan harvesting is fully complete and orchards enter postharvest management.
Typhoon preparedness. South China remains in an active typhoon period during White Dew. Strong winds and torrential rain can cause rice lodging, fruit drop, greenhouse damage, and losses in aquaculture. Farmers need to follow typhoon warnings closely and prepare preventive measures in advance.
Vegetables and aquaculture. Open-field vegetables across South China enter rapid growth and peak harvest. In aquaculture, typhoon season requires protection against flooding together with stronger pond inspections and water-quality management.
#### (2) Taiwan
Rice: In central Taiwan—including Changhua, Yunlin, and the Chianan Plain—the second rice crop enters heading and flowering during White Dew. In southern Taiwan, particularly the Kaohsiung–Pingtung region, the second crop also enters heading and flowering. In northern Taiwan, including Taoyuan and Hsinchu, the second crop enters jointing and booting.
Vegetables: During White Dew, sowing and nursery raising of autumn vegetables continue across Taiwan.
Fruit trees: Citrus enters fruit coloration, while bananas move from fruit development toward pre-maturity.
Tea: Autumn management continues in tea gardens across central and southern regions such as Nantou and Chiayi through autumn-tea picking, pruning, fertilization, and pest and disease control. Autumn management also continues in northern tea districts such as Wenshan and Sanxia.
Fisheries: Fishing continues in waters around Taiwan during White Dew. Typhoon season remains active and coastal areas maintain typhoon preparedness.
Farmer’s proverbs and folk customs: Taiwanese folk tradition preserves the saying “白露勿露身，早晚要叮咛”, a reminder that the weather turns cooler during White Dew and the difference between morning and evening temperatures becomes large, making warmer clothing important. Another saying, “白露白迷迷，秋分稻秀齐”, describes rice beginning to mature around White Dew and reaching full harvest around Autumn Equinox. There is also the custom of “白露吃龙眼”, eating longan during White Dew, when the fruit is abundant, as a way of nourishing the body.