Up here I bet the both would grow there. In the woods there are plenty of Redbuds and Dogwoods growing within five feet of huge trees so I know they'll survive.

For my yard I'd try to go at least 10 feet apart minimum just for personal preference. Eventually their crowns will touch and I feel the mix of white and pink flowers from dogwoods and redbuds will be attractive if they bloom at the same time.

I had a white ash and dogwood about 15 feet apart. Really the shade of the big ash didn't affect the shape of the dogwood hardly at all. I had a silver maple and redbud maybe 20 feet apart, the redbud still has a lean away from where the maple was and didn't grow much in its shade.

Two trees within just a few feet of a magnolia? Are you wanting a landscape or a natural foresty look?

IMO, it sounds like a mistake. Plant a bed with some nice appropriate perennials next to your magnolia and place the trees a good distance away.

Oh yeah...

You could always plant something temporarily until the magnolia matures a little. Use a few trees to fill in for now, and then remove/cut them when the Magnolia starts to fill in the space. Just be sure to follow through when the time comes.

how much shade can dogwood take and still flower well??

Would two hours of morning sun be enough(it would get high shade the rest of the time).

Thanks!

Oh, regarding the OP, I have two southern magnolias and yes,they are slow growing, so I did exactly what brandon7 proposes which is planting fast growing trees in front(because I need shade desperately,NOW,on that side) and so I have the shade for now, and when the magnolias start to get bigger(when I'm dead,lol!) then take down the others.

The dogwood back and center in this pic always flowered well under them two big ash trees.

I'd expect most to lean more towards the sun really and be thinner where in the shade.

{{gwi:460477}}

Thanks for the replies. I'm probably going to be in this house for 2 more years and just wanted the yard to look nice for now, however I don't want to create a nighmare situation for the next owners. I planted the Magnolia tree 4 years ago and I think it's grown about 2 feet during that time. So perhaps I'll take brandon7's advice and put in a fast growing tree such as a redbud until the Magnolia grows. I doubt that the house will still be standing by the time the Magnolia is big enough to cause any problems with the Redbud. Thanks for all the followups!