I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
The standard type of trailing lantana can usually go to zone 8b. With a good mulching in for winter you may be able to protect them and get them through just fine. There just is not a hardier type of the trailing lantana.
Thanks for the question. Please stop in again soon!
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