thidalgo

I live in North Mississippi and grow windmill palms. I am zone 7a. I have 2 that are 10+ feet tall. One has seeds for the first time this year. I have 2 that are 5 feet, and 2 that are 3 feet. The temp has been as low as 5 F since I have been growing these. The one gallon windmills are hard to keep alive. The first 2 I bought were 3 feet tall and they are over 10 after 10 years. I did nothing special and no mulch. I then bought 12 1 gallon. I planted them in a straight row at the edge of a pecan tree for protection. I mulched them heavily and lost 6 of them in the first 3 years. Once they were 2 feet tall with a nice trunk, I moved the remaining 6 to other areas in my yard. I did lose 1 that had a 1 foot trunk in the 4th year but I planted it in the shade. All the ones in the sun lived. If Oklahoma is zone 7, I would think they will live if you get one that is big enough and plant it in March. You could also cover the top with plastic so the top does not get water in the crown and freeze. The cold kills the small ones. Frozen water in the crown is what killed my larger one. I have never covered or mulched any of mine once they get a 1 foot trunk.