What does "full sun" really mean?

It means a minimum of six hours sunlight.

Yesterday a hummingbird hummed around my head then cruised slowly down the sideewalk checking out the ninebark blossoms & rhododendrons. We only have one kind of hummingbird in my zone & this one was smaller & merely brown so a little surprising; I presume it was a youngster. But it was quite startling because for a moment I thought I was being divebombed by a giant moth.

I once saw a not-too-bright hummingbird try to get nectar from cattail fluff, back up, then try again.

-paghat the ratgirl

Its means a minimum six hours of unobscured direct sunlight. No shade what-so-ever.

By definition, vines can never be in "full sun". The plants they grow upon for support provide some degree of shade, especially during the hottest part of the day.

Indirect bright sunlight would be more than enough for your plant.

We have 2 where I live.

beyond brown (though the photos you cite cause the memory instantly to ammend itself to reddish brown), but must've been the smaller rufus, just too young to have gotten any red or sheen on her. Maybe I'll see it a few more times & will be able to be sure. I just love such visits, & a few years ago started planting lots of hummingbird attractants because previously they'd hum through & not stay long because they didn't find enough to their liking.

-paggers

Ideal actually. The hot afternoon sun is no real friend.

If you have room the Chilean Fire Tree (Embothrium coccineum) is a great Hummer attractant and a spectacular blooming tree. They don't get very wide. They kind of look like a Eucalyptus. There is one in the Washington Park Arboretum.

Thanks and thanks to everyone who answered. I finally planted it today after thinking and rethinking the spot.

After all that, I planted it in the spot I originally picked out.

Giselle