I'm not sure this would be the best location for a lilac. All would prefer to be in full sun and you will generate the best flowering from such a position. And depending on selection, lilacs can get to be quite large shrubs in time - 15' tall and 8-10' wide is not at all uncommon for Syringa vulgaris, the common or French lilacs. There are dwarf lilacs available, like 'Miss Kim' or 'Tinkerbell', but to me they don't produce the same big flowerheads and intensity of aroma that old fashioned lilacs do.

But they all require more than a just a few hours of afternoon sun.

Lilacs are full sun plants. 'Some afternoon sun' won't be enough.

There are dwarf lilacs as mentioned, and I like them, but they don't have the same flowers as the full size shrubs. Smaller, narrower tubes, different fragrance. Full size lilacs are 10-15ft shrubs.

Sarcoccoca will take lots of shade, and is very fragrant, but in winter.

Sounds like a good spot for a rhodie or camellia or hardy fuchsia, but none of these are fragrant.

I simply do not have room for "real" Lilacs so I planted a 'Miss Kim' and though she isn't quite as fragrant and her flowers aren't quite as big, I do love her. She is about ten years old and under 5' tall and 4' wide. She does get almost full sun.

5-8 ft. Syringa x laciniata is a little more interesting because it has divided leaves.

bboy, I have never seen that one. I looked it up, you are right; interesting foliage. I'll keep my eyes open. I want a 'Tinkerbelle' too.

Thank you for information, i'll think about it.

I have five large lilacs in my front yard. I would like to downsize a couple of them but don't know if its safe to prune. They have never been trimmed and I need to know when to do it .
thanks

Lilacs aren't a shrub you can shear like boxwood or privet to keep smaller unless you want to lose the flowers....

You can prune out some of the suckers or oldest stems from the ground but trying to keep large growers small isn't going to work.

PS you should start your own thread instead of bringing up one that is several years old. You'll get more answers.