Oh, my, it is already September. In Australia it is considered the first day of spring.
September in Japanese is written as 九月 and read as くがつ (kugatsu), not きゅうがつ (kyuugatsu). Its old name is 長月（ながつき）.
There are a few theories why it’s called 長月（ながつき）but the most accepted explanation seems to be it is a shortened word for 夜長月（よながつき）, a month with long nights. In the norther hemisphere, it is beginning of autumn and people would have noticed that nights start to get longer and longer in September.
September is also called 菊月（きくつき）, a chrysanthemum month – this is self-explanatory as you can see lots of chrysanthemum in Japan in September. 菊 is one of the most praised flowers in Japan and it is the family crest of the Imperial family.