The "wind vane" of Shanghai osmanthus season has finally returned to normal, and the flowering period has been disrupted for three years
The first wave of osmanthus bloomed in Shanghai this year.
On September 11th, a reporter from Jiefang Daily's Shangguan News learned from the Shanghai Botanical Garden that the early silver osmanthus has bloomed extensively in the garden. Good news has also come from parks such as Guilin Park, Dong'an Park, Jing'an Sculpture Park, Daning Park, and Zuibaichi Park.
Early silver osmanthus is the most commonly cultivated variety of silver osmanthus in the Yangtze River Basin. It has an early flowering period, light yellow white flower buds, and yellow white to milky yellow flowers when in full bloom. It has a strong aroma and high ornamental value, and is known as the "wind vane" of the Shanghai osmanthus season.
"The earliest blooming plant is the early silver osmanthus, located in the osmanthus garden near Gate 3 of the park. It was discovered on August 31st and its initial flowering period is within the normal range. Generally, the normal flowering period for early silver osmanthus is from the end of August to mid September." Wang Yuqin, a senior engineer at Shanghai Botanical Garden, said that after flowering, the viewing period for early silver osmanthus usually lasts about a week.
![The "wind vane" of Shanghai osmanthus season has finally returned to normal, and the flowering period has been disrupted for three years](https://a5qu.com/upload/images/c8843e06891593fc05f63d8b285a0a71.png)
Shanghai Botanical Garden Early Silver Osmanthus
Many people are unaware that it is rare for silver osmanthus to bloom during its normal flowering period this year. In recent years, the flowering period of osmanthus in some parks and green spaces in Shanghai has been somewhat chaotic.
On July 20, 2020, the early silver osmanthus in the Shanghai Botanical Garden opened, marking the earliest phenological record in the garden.
However, in 2021, the early silver osmanthus period in the park experienced a "major reversal", dragging on until September, more than two months later than in 2020.
![The "wind vane" of Shanghai osmanthus season has finally returned to normal, and the flowering period has been disrupted for three years](https://a5qu.com/upload/images/48788723a9c7b88096839f0b2a25b6ef.jpg)
Unexpectedly, one year later, this "latest record" will be broken. The first osmanthus of the 2022 Shanghai Botanical Garden osmanthus season was not discovered until September 26th. In the eyes of the "old wizard" who has been cultivating flowers for many years, the early flowering of early silver osmanthus to mid July or late flowering to late September is a "historic breakthrough".
For such abnormal initial flowering time, Wang Yuqin said that the specific reasons still need to be studied, and it is speculated that it may be related to the changing climate in recent years.
After years of observation, recording, and data analysis, the flowering of early silver osmanthus needs to meet the conditions of "suppressing first and then rising": first, there must be "autumn atmosphere", and when the temperature drops below 21 ℃, the flower buds can transform into flower buds; Afterwards, the enlargement of the flower buds requires warmth, and professionally speaking, the accumulated temperature in four to five days should reach 150 ℃ or above.
Taking the early silver osmanthus, which bloomed the earliest in the history of Shanghai Botanical Garden in 2020, as an example, in mid July of that year, Shanghai experienced the "longest rainy season for plum blossoms in this century". As soon as the plum blossoms appeared, the temperature rose, but the air humidity was relatively humid and stuffy. In addition, the previous period was sunny and rainy, and the reduced temperature and increased air humidity turned on the "osmanthus steaming" earlier, making the osmanthus foolishly think that autumn had arrived, meeting the conditions for osmanthus flowering to "suppress first and then rise". Compared to July 2020, the relatively hot weather in August and September 2021 and 2022 prevented osmanthus from hearing the "starting gun" of autumn coolness, and it was almost the National Day holiday before they realized it.
![The "wind vane" of Shanghai osmanthus season has finally returned to normal, and the flowering period has been disrupted for three years](https://a5qu.com/upload/images/34f0b7e060e8e8fdec84cec088eb4313.jpg)
Wang Yuqin said that overall, in recent years, the initial flowering time of Shanghai osmanthus has become increasingly early. In recent years, the earliest blooming time of osmanthus in Shanghai Botanical Garden has been from September 22, 2017 to September 13, 2018, and then to September 5, 2019 and July 20, 2020, which can be said to be getting earlier and earlier. This is related to the variable climate of "playing cards without rules". But if the weather becomes hotter and hotter in the future, it cannot be ruled out that the initial flowering time of osmanthus will become later and even become a trend for many years to come.
After the early silver osmanthus, there were early flowering varieties in the group of osmanthus varieties that took over. Among the four season osmanthus varieties, there were Fo Ding Zhu Gui, Yue Yue Gui, and Da Ye Si Ji Gui, as well as Bo Ye Jin Gui and Hangzhou Huang Gui in Jin Gui. Among them, the most colorful ones include the red osmanthus from the Dan Gui series and the Yan red osmanthus.
From left to right, there are Dan Gui, Jin Gui, and Yin Gui, and color is one of the methods to distinguish them