1. The first time is within a few days to two weeks after the flower withers, it falls off with the fruit stalk, commonly known as "falling flower". The main reason is poor fertilization and lack of growth hormone for pollen transmission.

2. The second time is one month after the flowers wither, and the time is in June, which is also called "falling fruit in June". The main reasons are insufficient nutrition and lack or imbalance of endogenous hormones; Too much water or drought can also lead to fruit drop in June. This fruit drop has a great influence on yield.

Introduction:

First, the growth environment:

(1) temperature description: the growth, flowering and fruiting of citrus fruit trees are closely related to temperature, sunshine, moisture (humidity), soil, wind, altitude, topography and slope direction, and these conditions have the greatest influence on temperature. Even if the temperature difference is 0.5℃, sometimes there will be completely different results. The growth and development of citrus fruits need a temperature of 65438 02.5 ~ 37℃. The day and night temperatures of flower bud differentiation in autumn are about 20℃ and 65438 00℃, respectively, and the soil temperature of root growth is roughly the same as the ground temperature. If the temperature is too low, oranges will freeze. When the sweet orange is at -4℃ and the satsuma orange is at -5℃, the branches and leaves will be frozen. When the sweet orange is below -5℃ and the satsuma orange is below -6℃, the branches will be frostbitten. When the sweet orange is below -6.5℃, the satsuma mandarin will freeze to death.

(2) Lighting environment: Citrus is a tree species with strong shade tolerance, but good sunshine is still needed for high quality and high yield. Generally, areas with annual sunshine hours 1200 ~ 2200 hours can grow normally. For example, compared with Chongqing citrus producing areas with less sunshine, South China with good sunshine and abundant calories has higher sugar content, lower acid content and higher sugar and acid content.

(3) Humidity introduction: Generally, tropical and subtropical regions with annual rainfall of about 65,438+0,000 mm are suitable for citrus cultivation, but irrigation is often needed because of uneven distribution of annual rainfall. The suitable relative water content of soil is 60% ~ 80%, and irrigation is needed when it is lower than 60%. Too much rain will cause soil water accumulation or high groundwater level and poor drainage in citrus orchards, resulting in root death. Citrus fruit trees require that the air relative humidity should be around 75%.

(4) Soil environment: Citrus can adapt to a wide range of soil. Purple soil, red and yellow soil, beach and tidal flat can all grow at ph 4.5 ~ 8, and ph 5.5 ~ 6.5 is the most suitable. The growth of citrus roots needs high oxygen content, and the soil with loose texture, good structure, organic matter content of 2% ~ 3% and good drainage is the most suitable.

Second, the efficacy and role:

1. Decoct orange peel and ginger slices with water and drink their soup to cure stomach cold and vomiting.

2. 30 grams of raw orange peel and 6 grams of licorice can be used to treat mastitis.

3.12g fresh orange peel (or 6g dried orange peel), decocted and taken, can cure constipation.

4. Chewing raw orange peel can cure bad breath.

5. Orange peel decoction or juice can sober up.

6. Orange peel soup can detoxify fish and crabs.

7. Fresh orange peel is soaked in boiling water and added with appropriate amount of sugar, which is orange peel tea. After drinking, it can regulate qi and relieve bloating, promote fluid production and moisten throat.

8. Wash fresh orange peel, cut into pieces, and soak it in China liquor to make orange peel wine, which is fragrant and mellow. Drinking a small amount every day can clear the lung and resolve phlegm.

9. When children's digestive system is dysfunctional, taking orange peel soup can help children digest food and promote appetite.

10. Adults can also eat orange peel for treatment when they have symptoms such as anorexia, chest pain and excessive phlegm.