I do think its a bit too late to plant this year, so I would just keep them in pots for this summer and plant them out next spring. Remember to keep them well watered and bring them in when temperatures start dipping down to the mid to low 20s. You can keep it in an unheated garage after that if you have one. Then sometime right around the last frost date (day temperatures in the 50s and nights in the 40s) you can plant it outside and watch it grow for next summer!

Wish I could tell you that you could plant it now, but it really is best to wait.
-Alex

I have bought and planted minors and windmills from them discounted in September with no problems. You would want to protect it this year.

Good luck,

I agree,at the very least keep moisture out of the crown.
I have planted Trachys as late as Nov/Dec(with protection)
and not had any problems.
Go ahead and plant it/them. (-:

Trachycarpus can be planted later than Rhapidophyllum. Dig a hole and drop the Needle in, pot and all. Next spring, plant it permanently.