Retics are more tender than Japonicas and Sasanquas. I would encourage you to get in touch with the members of the Camellia Society of the Potomac Valley, who are from your area and are all very knowledgeable and delighted to help, including Dr. William Ackerman who has been very active in experimenting with cold hardiness in different varieties and hybrids there in DC/Maryland. (See link below.) You are fortunate to be near them.

Here is a link that might be useful: Camellia Society of Potomac Valley

i have been growing several retic hybrids in central alabama and have been quite successful. the largest is a clear pink called 'lila naff'. its loaded with buds now, but usually blooms later in feb. i planted it as a small one gallon plant 12 years ago. it is over 10 ft tall and nearly as wide.

Oh yes, the retic hybrids do well in our Alabama climate, aren't they wonderful! I don't know about Maryland, though, especially outside. Here along the gulf coast we can also grow some pure reticulatas, of which I have a few and would love to have more. They are not so easy to find.

Could someone please answer the original question? What is the northernmost zone in which Reticulatas will thrive?

Steve--I've tried growing some Reticulatas and R. hybrids outdoors without success here in 7a--they just don't make it through the winter even with protection. As a compromise, I've grown a couple of them in pots which get brought into my cool sunroom for the winters. Well worth the effort--Clifford D. Parks is simply the most astounding bloom I've ever seen. Kai Mei's Choice also does well in the pot. They're kind of straggly, but Reticulatas grow that way--not in an unattractive way, but definitely less full than the Japonicas I also grow in pots. And, bonus! they start their bloom in the sunroom in February when everything outdoors is still dormant and ravaged by the dingblursted deer. Indoors, the blooms individually last about 2 weeks on the bush and by the time they finish up, things get going outdoors. Give it some thought.

-eric