cold hardy citrus
I have a place between Houston and Dallas and would like to plant a few citrus tres outside there. The temperature normally doesn't drop below 20 during the winter at the coldest. I am planning on planting some Satsuma oranges. I was wondering if there were any lemons or grapefruit that would survive the cold up there. I don't live there so I can't plant them in pots and bring them in and out. In Houston my Navel oranges have survived 20 degree weather without any protection other than what is provided by the house. Up there they would be pretty much exposed.