Citrus x meyeri or commonly called the Meyer Lemon tree is a gorgeous evergreen citrus tree originally from China that is a hybrid between a common lemon tree and a mandarin orange tree. It was first discovered and sent to the United States in 1908 by Dutch horticulturist and botanist Frank Meyer who was working for the United States Department of Agriculture. Unfortunately, the original Meyer Lemon Trees were found to be susceptible to a devastating virus called Citrus Tristeza and eventually became symptomless carriers of the said virus, which infected and killed millions of citrus trees across the United States and all over the world. Because of this, most Meyer lemon trees have to be destroyed. A surviving and virus-free Meyer lemon tree was then discovered by Don Dillon in 1950 and was later certified and released by the University of California as the Improved Meyer Lemon Tree in 1975. The Improved Meyer Lemon Tree is cold hardy and best grows in US Department of Agriculture USDA hardiness zones 8 to 11. It is fairly vigorous, shrubby, and somewhat small in size upon reaching maturity standard Meyer lemon trees can grow as tall as 6 to 10 while the dwarf lemon tree can grow up to 4 to 6 in height. This lemon tree variety has a spreading habit and is nearly thornless making it a great citrus tree to plant if you have kids, be it indoors or outdoors. This citrus tree blooms purple-tinted flowers all year round but blooms are more concentrated in spring or fall. The fragrant blooms then turn to medium-sized, orange-yellow, juicy sweet-tart lemons that are in season in fall/spring.