What season is Sagittarius?

According to this calculation, Sagittarius can be seen in the south at midnight. Actually, Sagittarius is very south. For most parts of China, Sagittarius can rise above the horizon in a short time. In fact, Sagittarius and Scorpio can only be seen in the south at eight or nine o'clock in the evening from August to September every year.

I think this error may be caused by the size of the constellation crossing the ecliptic. Virgo is the second largest sign in the whole day, occupying more space on the ecliptic than other zodiac signs. In addition, part of the zodiac is in Ophiuchus, but Ophiuchus is not a zodiac sign.