I think you may be referring to a kumquat simply known as 'Meiwa', and if I'm wrong, please do correct me before reading further because I will be going on and on about Fortunella crassifolia, or Meiwa!
I have had the cutest little Meiwa kumquat tree for several years now. It is likely a dwarf as it has not grown past 3 feet tall, but it has dark green leaves and plenty of them, and fruits proliferously. Flowers throughout summer, fruit starts growing very quickly and they turn orange by December/January.
Even before the fruits turn orange, I've found that they are already sweet--color can be deceiving! Size tells you a bit more than color when it comes to these kumquats.
Miss Hibiss
Martin WeberOriginal Author
Miss Hibiss
tom1328732
Silica