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.
Kumquats love full sun although they can take a little late day shade just fine. They are hardy (compared to most citrus) and can take cold down to about 24 degrees before damage will occur. However in a container the roots may be damaged by extended freezing temps since they are not protected by the soil's heat. That said, a 30 gallon pot is large and should be able to hold enough heat to withstand some cold. To be safe, move the plant in on a dolly or other device when temps drop to the mid to upper 20's.
Thanks for the question. Please stop in again soon!
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