It's strange, but I have every shrub you are referring to, so I hope my experience with these shrubs is helpful.

I have a PeeGee Hydrangea tree, it's about 5 years old, and it is gorgeous. However, because the blooms are so full and heavy, after getting rained on, most of the flowers will droop down. There are ways to prune the tree so that the branches get stronger, which I have been doing, but I am not seeing much improvement. For more information you should look at the Hydrangea forum.

I also have 2 other types of hydrangea trees: a Pink Diamond (also has beautiful and large blooms, but they are less dense, so they are lighter and they do not droop after rain, and the white blooms turn a pretty pink as they age), and a Limelight hydrangea (these are more similar to PeeGees than the Pink Diamond, but they seem to be less prone to drooping.)

My PeeGee and my Pink Diamond are on the north side of my house (zone 5, Michigan), and they do very well there. I wonder if your southern exposure will be too much sun for them. My Limelight is on the south side of my house and it is doing well there. And I've read that Limelights do well in part to full sun.

I've seen snowball viburnum standards, and I think they are gorgeous! I know they do well in full sun because I have a bush in full sun and it's growing nicely.

I also have a Merril magnolia (which I think is similar to Stella) on the south side of my house. It produces fragrant white, daisy-like blooms in early spring. It is not a fast grower, and it seems like it would be easy to keep it pruned to the size you want. However, this shrub, like other magnolias only stands out in the landscape in early spring, after that, it is kind of boring.

So, I think if you want something eye-catching, for a long period of time, the best choice for you would be a Limelight hydrangea tree. The flowers last from early summer through fall, they don't tend to droop, they are easy to prune, they like full sun, and the flowers start out a beautiful greenish-white, then they turn all green.

You may want to look at the Hydrangea forum, it includes alot of information about the various types of hydrangeas.

Another small tree that should work is Xanthoceras sorbifolium--Yellowhorn. It gets about 10 feet tall and is airy with very early, very striking spring bloom. Frost is never a problem. No fall color however.

BTW, your tree as shown seems much too close to the house. Any of the tree/shrubs you mention get large enough that they should be at planted at least 8-10 feet from the window, so it's not crammed up against the house and window when it's mature.

Have you thought about a weeping cherry tree? I have one infront of my double window and it is absolutely beautiful! I also have a dapple willow infront of my other window that is beautiful when in full bloom and it works well in both cold and warm zones.

Some great suggestions! Yeah, I almost put in that whatever is planted will be moved out farther from the house - at the time I was just putting something there to replace a shrub that the original owners had there.

I'm going to look into the Limelight and Yellowhorn. Carefree I already have a weeping cherry on the right side of the house or that would have been perfect!

Yesterday at Lowe's I saw a tree-form Lilac bush. Any opinions on those?

May I suggest a Rose of Sharon Tree. It is so easy to grow and it blooms while everything else has stopped.

I have the "typical" lilac shrub trimmed up to a tree form, and it was here and established to maturity when we moved in. It gets very large, and is susceptible to mildew, so a more open airy space would be ideal rather than next to a house. Most lilacs are pretty slow growers.

I've considered Rose of Sharon for the front of my house in the past, until I realized they are slow to wake up in the spring. Most other plants are budding and/or blooming, from what I've been told, before this breaks dormancy.

Peegee Hydrangea tree is supposed to love full sun. It's on my list for my garden this year.

If you want to add a little color to your landscape, I also like Purpleleaf sandcherry shrubs (not tree form). They grow pretty fast, love full sun, nice blooms in the spring. I trim the tops back for a "fuller" bushy look, and on others, I trim them "up" to more a tree form, more room for underplantings. They need to be pruned annually, after bloom time, to encourage growth. You might not like the "legginess" if it's trimmed up though.

Last thoughts are burning bush or Hakuro Nishiki Willow on a standard. The Willow is a nice eyecatcher in the landscape.

Have fun! :)

Aaaaack. Didn't see how old this post was before I submitted.