I haven't posted in a few years so forget how to do photos now, but I'm sure somebody will happen along to help you with that.

However, I do have a similar situation in my back yard with a large pre-existing maple tree and neighbors behind me (we have a corner suburban lot, way smaller than yours, but still want to screen the back line for privacy). Forsythia was in part of the back yard on that back line, but that became too messy and lots of work (required taking out dead wood every year) and I wanted some evergreen screen like in other parts of the back line. So, I transplanted some arborvitae there that was getting too large elsewhere, and some of them are doing OK while others are not.

So I decided to go with the most indestructible evergreen that I know of...euonymous. Euonymous does well in any light situation, and sounds like it will get at least 1/2 day sun once the sun has passed over the large trees. You can get it in plain green or with gold or white variegation, and you can get euonymous major (which will reach 15 - 20 feet or so) or minor (which is more groundcover/viney climbey).

If I were to start from scratch as you have, I would line the back 5' of the kidney shape (that you have indicated is empty) with Euonymous Major in Green, which would give you a plain screen for the back. They grown well in sun or shade, just slower in shade. They will grow slower at first than the hydrangeas (so don't freak out the first couple of years if you can't see them once the hydrangeas take off in spring), but they are very adaptable to water or lack of water once they're established.

Then, in front of the green screen I'd put one or 2 or even 3 (3's look nice) spread out Gold Spot Euonymous Major, just to have some color in the winter, and maybe a couple of hollies for the 3 season interest (white flowers in spring, then green berries in summer, turning red in fall/winter). The hollies will attract birds also if you like birds (I do).

You'll still have plenty of room in front of those for your flowering shrubs and perennials. I'd have my furthest back center in front of the evergreens be an Oak-leafed hydrangea that will grow to 10 - 20 feet tall, to give the back a peak shape in summer (sort of creating a triangle with the large trees), many of those have white flowers which will pop out well from the shade of the oak and maple.

To either side of that, I'd try some Hydrangea Paniculata, like Pinky Winky, which will get 8' tall and just as wide, with huge pink panicles. Then in front of those, I'd start filling in with the shorter hydrangeas that you have, maybe spreading them out and alternating the SI instead of having it all in one place.

I'll try using your method to describe and use the plants you've listed that you have in addition to the ones I've suggested. Your bed is almost the size of my entire lot, so my back bed is much more narrow and consists only of the euonymous with hydrangeas in front and some hostas sprinkled about, not enough sun under the maple for iris or peonies.

ALso, I think your peonies should be behind the iris, they'll get too tall and you won't see the iris anymore. One thing to be careful of is to not put TOO much soil near the base of the big trees, you could create a problem if you smother them. I have put a few inches of soil at the base of my maple and grow hostas and daylilies in it, but I wouldn't put much more than that around those tree bases. But you could probably leave all the woodland type things under the tree area where you have them.

Ok, adding E - eounymous, GE - Goldspot Euonymous, H - Holly (variegated ones are really pretty, harder to find but worth it), and OH - Oakleaf hydrangea, PW - Pinky Winky hydrangea. So here goes nothing:

E..........E.........E.........E..........E............E..........E...........E...........E..........E

Maple...............GE.......................GE..................GE..................Oak

................H.................H......................H...................H..................H

...................PW..............................OH................................PW

..............LC LC.............................BB BB............................. TD TD
.................LC................................. BB....................................TD
KO..................................................................................................KO
...............................P P....................................... P P.........................
............SI SI........................... BSI BSI.................................SI SI

I hope the spacing works here on the post. In between and in the front there should be plenty of space to add some annuals each season for continued interest, or even a few Knock Out roses (KO - which are easily sheared with shrub shears), which will give you 3 or 4 flushes of bloom each year. Of course, I'm not a landscaper but have been working on my garden/s for 12 years now and have picked up a few things along the way.
Whatever you decide, have fun with it! Yes, it's never REALLY done since we gardeners tend to like to tweak things, but just have fun with it!

1. Oak tree on right side of bed. View of neighbors property behind the bed. Tree (hickory) on left of pic is on my property but not in the bed.

2. Maple tree on left side of bed. To he left is the side neighbors swampy yard. Water runoff comes from the 3 acres from back neighbor. Tree on the right of pic is the hickory again - not in bed.

3. Perspective pic taken from top of driveway. Pull to the top of the drive - this is what you see.

4. Taken from behind oaktree showing the bed in relation to driveway. Perspective is from back to front of property.

5. Perspective from driveway again but pic taken closer up.

6. This perspective is moving over towards the back of the house. What I see from the kitchen but a close up view of it.

7. Pic taken further away from the bed towards the back of the house. Dirt mound is another project. Ignore that.

8. Another close up. Out of focus.

9. Green lawn on left is next door neighbors swampy yard. Good perspective on the 3 acre property behind.

10. Pic taken from perspective of the driveway again.

So, that's it. The overview. The bed is kidney shaped roughly 50' x 20'. It's deepest on the maple side/left side.

What I want to do is blend visually into the property behind. I couple of trash piles back there that I could screen out but otherwise a beautiful view. I don't want to get too fussy with what I do in the bed.

Maybe the peonies should come out of there? It's a woodland setting afterall. I can find another place for the peonies and iris.

Then, back to front - a couple of hemlock planted on top of the ground on either side of the hickory. Nice screening and graceful. A couple of dogwood with redbud or just some sourwood. Coming forward - several scattered rhodos. And finally some of the LC hydrangea more towards the front of the bed. Generally speaking ...

Comments welcome.

ML

ps Razorholik. Thanks for your input. I replied and lost the whole dang post. Hope these pics help set the scene.

It is a lovely view and your bed is lovely. I'm not sure which Hydrangea you have so can't say how big their ultimate growth is, but they might be the smaller ones and some lacecap don't do well in Ohio with dieback. If so then I would put taller shrubs in back for the height, keeping in mind they will fill in the width to the back of the bed, but nothing to high or they are going to grow into the canopy of the trees and lose the neat look you have now. If you want evergreen, there are also evergreen Holly to consider that only get around 8 foot high, be careful in researching that you get the right ones. Or deciduous shrubs are also a possibility, but with so much shade the Hollys are a good choice for evergreen.
Cher