Kumquat is oval in shape, 3/4" to 1" in diameter and between 1" to 2" long. The tartness of the fruit makes them great for use in cooking and/or for marmalades and jellies.
The Nagami or Oval Kumquat (Fortunella.margarita) is the most common variety in the United States. It was introduced into Florida from Japan in 1885 and has been grown commercially in the "Kumquat Capitol," Saint Joseph, Florida since 1895. The Nagami Kumquat is oval in shape, 3/4" to 1" in diameter and between 1" to 2" long. The tartness of the fruit makes them great for use in cooking and/or for marmalades and jellies. The tree is shrub like and is similar to an orange tree in appearance. It is a prolific bearer and very decorative because of the dark green leaves and brilliant orange fruit. The fruit lasts for several months on the tree in warm winter climates. The trees do very well when planted in the yard or in larger pots. They can withstand temperatures as low as 28 degrees and require about the same care as other citrus. They can be grown throughout Florida, but produce larger and juicier fruit when grown in the sandy soils on the hills of eastern Pasco County in central Florida. The kumquat tree is highly resistant and possibly immune to citrus canker.