This study investigated phenological changes, shoot growth, and flowering habits of potted kumquat [Fortunella margarita (Lour.) Swingle] grown in subtropical conditions of I-Lan County, Taiwan. The shoots of the second, third, and fourth flushes of kumquat sprouted in mid-May, early July, and early September, corresponding to 70-80, 112-122, and 168-178 days after the buds sprouted from the first flush, respectively. As the flushing sequence progressed, the number of shoots, the rate of flowering, and the number of flowers decreased. There were four flowering peaks in 2010 and five in 2011. The shoots of the secondary and tertiary flushes still bloomed in 2010, but they did not flower in 2011. In 2011, the second flowering period of the first flush shoot, which flowered in mid-July, fruit set, and fruit growth showed the best performance, and the whole fruit development duration took about 169 days.