Answer: Archontophoenix cunninghamiana, King Palm, is a stately palm can best be described as clean cut. The trunk and leaves are smooth green above and a little grey below. The leaves can be 10 to 15 feet long and a King Palm can grow to 50' tall if it is happy. Young trees can be killed by temperatures colder than 28 degrees. Older tree's leaves will be damaged at that temperature and can be damaged by wind. The fronds are held out well until they drop.
Arecastrum romanzoffianum , Queen Palm, is a large palm and can grow to 50 feet. The leaves are graceful and arch, where the King Palm leaves are rather rigid. The leaves can grow 10 to 15 feet long. It is damaged by frost in the high 20's though I have seen survivors of 18 degrees.
Both palms are attractive; King has a more palm tree appearance with rings around its trunk. The Queen has a more delicate and tropical appearance. Hope this information helps you decide!
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