It is expected that the apple flowering period in most production areas will be the same or earlier, and some areas need to prevent moderate risk of freezing damage

According to the early-warning results of the big data deep mining and analysis system of the whole industry chain of Apple in the Information Center of the Ministry of Agriculture and Rural Affairs, in 2023, the main apple producing areas in northern China will enter the flowering period from south to north on March 31. It is expected that the initial flowering period of most apple producing areas will be concentrated in early and middle of April, the central and eastern producing areas will be the same or 1-5 days earlier than usual, and the central and western producing areas will be 1-3 days later. As the flowering period in most production areas this year is the same or earlier than usual, the early flowering period is vulnerable to the impact of low temperature freezing damage. According to the China Meteorological Administration, from April 1 to 5 and from April 12 to 14, there will be a wide range of temperature drop throughout the country. The lowest temperature in the producing areas of Fuxian County in Shaanxi Province will reach -8℃, and the risk level of frost damage in some producing areas of Shaanxi, Shandong, Gansu and Shanxi Province will be moderate. Other producing areas were mild.

1. The initial flowering period in Shaanxi producing areas is concentrated in early and middle April, and the risk level of frost damage in the flowering period is moderate

The early flowering period of apples in Shaanxi production areas is mainly in early and middle April. The first flowering period in Weinan area came on April 2-3, Pucheng, Dali, Fuping and other producing areas were 1-2 days earlier than usual, while Baishui producing area was 1-3 days later than usual. Yijun production area in Weibei area entered the first flowering period on April 3rd, 1-3 days earlier than usual. Guanzhong area enters the initial flowering period from April 4 to 5, Xunyi, Yongshou, Bin County and other producing areas are slightly delayed compared with the usual, Fufeng, Qianxian, Liquan and other producing areas are 1-3 days earlier than the usual; In northern Shaanxi, Fuxian County, Luochuan, Huanglong, Huangling and other producing areas will enter the initial flowering stage on April 8, 1-3 days earlier than usual. Zhidan, Suide, Yanchuan and other producing areas will enter the initial flowering stage in mid-April, 3-5 days earlier than usual. According to the weather forecast data, there were low-temperature rainy days in the first and middle of April in the whole province, among which the lowest temperature in Fuxian producing area reached -8℃ on April 14, and the risk level of frost damage in the flowering period was generally moderate. The key defense period in Guanzhong and eastern Weibei producing area was in the middle and middle of April, and the key defense period in northern Shaanxi producing area was in the middle and late of April.

2. The flowering period of Shandong producing areas is earlier than usual, so the influence of low temperature on pollination should be prevented and controlled

The initial flowering of apple in Shandong producing areas was earlier than usual. Juye producing area in Southwest China entered the first flowering period on April 3, 1-3 days earlier than usual. In the central region, Yiyuan, Xintai, Pingyin and other producing areas entered the first flowering period from April 6 to 8, which was 2-4 days earlier than usual. The Huimin producing area in Northwest China entered the first flowering period on April 12, 3-5 days earlier than usual. In the eastern region, Longkou, Laixi, Haiyang and other producing areas will have their first flowering period from April 13 to 14, 3-6 days earlier than usual. Most other producing areas will have their first flowering period from April 17 to 19, and Qixia, Penglai and other producing areas will have their first flowering period 4-6 days earlier than usual. According to the weather forecast data, the temperature of the whole province in April was slightly higher than that of the same period of the year. There were two cooling processes on April 7-8 and 12-14, among which, the lowest temperature in Huimin producing area reached 0℃ on April 14. Therefore, it is necessary to focus on preventing and controlling the influence of low temperature in flowering period on pollination quality and fruit setting rate.

3. The flowering period of Gansu producing areas is earlier and later than usual, so the risk of freezing damage should be prevented

In most Gansu province, the temperature in February was higher than usual, while the temperature in March was lower. The first flowering period of Lixian County, Qin 'an and Gangu in the South of Longnan region was from April 4 to 6, which was 1-3 days later than usual; Jingchuan, Zhuanglang and Lingtai were from April 8, 1-2 days earlier than usual; Heshui, Jingning, Qingcheng and Zhengning were from April 12 to 16, which was 1-3 days earlier than usual; Zhangjiachuan, Gulang and other producing areas in Longzhong area will enter the first flowering period around April 7, which is about 3 days later than usual. Attention should be paid to the risk of frost damage in areas with early flowering period. Attention should be paid to the influence of low temperature of -2℃ in mid-April and continuous rain in Tianshui producing areas.

4. The flowering period of Shanxi producing areas is the same or slightly earlier than that of the year, and the risk level of frost damage is moderate

Pingyao County, Jinzhong Prefecture, entered the first flowering period on April 13, two to four days earlier than usual.

5. The flowering period of Henan producing area is earlier than usual, so beware of the influence of rainy weather on fruit setting rate

The first flowering period of apples in Henan producing areas is 2-5 days earlier than that in normal years. Lingbao City had its first flowering season on March 31, which was 2-4 days earlier than usual, and Eastern Henan (Mianchi, Tongxu, Xianyi, Lankao and other producing areas), Western Henan (Mianchi, Luoning and other producing areas), northern Henan (Nanle, Hua County, Neihuang and other producing areas) had its first flowering season on April 2-4, which was 2-5 days earlier than usual. According to the weather forecast data, the lowest temperature in April is above 3℃, the risk of frost damage is low in the flowering period, but the temperature and rain weather around April 12, beware of the influence of low temperature rainy weather on the fruit rate of apple.

6. The flowering period in the producing areas of Hebei is earlier than usual, and the northern part needs to guard against reverse spring cold

In Hebei producing areas, the temperature in February and March was higher than that of the year, and the first flowering of apple was earlier than that of the year. The first flowering period in Xingtai production area in southern China was on April 10, which was 2-4 days earlier than usual. The first flowering period of Shunping in the central region was on April 13, 2-4 days earlier than usual. In the northern region of Chengde, the first flowering period began on April 19, 1-3 days earlier than usual. According to the weather forecast data, the lowest temperature in the southern region will remain above 3℃ after April 5, and the risk of frost damage in the flowering period is relatively small. In the northern region, the temperature will drop greatly from April 13 to 14, among which the lowest temperature in Chengde production area is -5℃, and the risk level of frost damage in the flowering period is moderate. Special attention will be paid to the mountainous areas and low-lying orchards in the north, such as Zhangjiakou, Chengde and the northwest of Baoding. It is necessary to prevent frost damage in flowering period caused by local microclimate change.

Based on the above monitoring and prediction, it is recommended that local governments pay close attention to weather changes and take measures according to local conditions to prevent and reduce the impact of low temperature freezing damage on apple production. Pay attention to the early warning information of freezing damage in real time and improve the awareness of freezing damage prevention in orchards; Spring irrigation, white coating and other ways can be used to delay the flowering time of fruit trees. Before the onset of frost damage, tree crown spray, smoke, spray antifreeze and other measures to prevent frost and reduce the risk of frost damage; In view of the influence of low temperature on pollinator activity, it is suggested to do artificial pollination. Post-disaster remedial measures should be taken, such as spraying growth regulators and foliation fertilizer, strengthening pest control and comprehensive management of soil, fertilizer and water.