Fukushu Fortunella obovata hort. ex Tan. Kumkvat
Fukushu SRA 325, Fukushu-kinkan, Changshou, Changsou, Chin Chü, Choju kinkan, Chojukinkan, Jiangsu, Kantonský kumkvat, Obovato
This kumquat is sometimes also called "Canton Kumquat" and it originates in China. It is a very old variety and the word "changsou" means "long-lived ". This cultivar is renowned for its extremely slow growth.
The tree itself is very compact and has lots of leaves with no thorns on its branches. It resembles kumquat 'Nagami' very much, but is more vigorous, has slightly larger leaves and tendency to make too many branches that usually don't bare any fruit. According to many opinions this could be a cross of oval kumquat F. margarita (Lour.) Swingle.
The fruit is small or medium (2-5cm), quite wide and usually oval. Its rind is almost golden yellow, when fully ripe, thin, smooth, sweet and edible. The pulp is light orange and is quite soft, somewhat hot like chili with lovely resin-like aroma. There's usually about 5-9 segments in each fruit and very few thin, polyembrionic seeds. Fukushu's fruit can be eaten along with the rind (precisely like other kumquats) or they are usually preserved in jars.
Just like other kumquats even this one is fairly cold-hardy and suitable for growing indoors. It likes pots and is ideal for growing in drier flats. What this variety really dislikes is wet climate, because of its high susceptibility to Mallattia crittogamica.