THE plant for dry shade--Geranium macrorrhizum--big Root Geranium. Semi evergreen, handsome groundcover, highly deer resistant, easy to control, very attractive with late spring bloom and no dead heading, dividing or other attention required. What more could you want? Alternate--Epimedium sulphureum--slower to fill in, must be cut back in late winter, but very attractive and has early bloom. If you garden in deer country, as I do, there is very little point in planting plants that deer love. It's a losing battle. And while it is true that starving deer will eat anything, there is a huge range of plants for both sun and shade that they generally have very little interest in. If your yard has mostly unappealing plants, they won't hang out there much. That said, I ALWAYS spray a new plant with a good repellant so if some young thing tries it, their first experience is YUCK! They spread the word. And having said all that, yes, I do have a few plants that deer will eat, and I do spray those. But they are very few, so keeping up with the spraying is not onerous and doesn't break the bank. However, I have NO hostas, yews, or tulips--the ones that say "Free Lunch".

more tall perennial suggestions: crocosmia Lucifer Japanese anemone meadowrue, Thalictrim find a native flowering/fruiting shrub or tree in your area to attract birds add a bubbling fountain or bird bath Remember on the other side of a fence can be a cold pocket especially on the north. Do not feed them after August. Mulch well to overwinter them. Hosta & Astilbe will do fine. Lamium might not, but usually bounces back from roots. Several plants with snow on mtn common name, so not sure which one. I hope you didn't plant Aegopodium podagraria 'Variegatum' because it is a spreading thug only suitable for a place by itself. I've removed it from a garden when I realized the spring planting was a bad idea. I do have it in another area and have to keep an eye out for blooms to prevent reseeding and shovel prune the edges to keep it in bounds. Another way to give height is to mound the bed or add graduated size boxes made from fence wood. The center would be tallest and can be offset. If your bed is 5-6 feet wide you won't be able to mound it much, but some helps. I try to middle mound all my beds for that berm effect that I prefer.

Lilacs require a cold winter to flower well and perform much better in full sun. Beautiful flowers - I have several in different colours. All are old plants but nowhere near 4m high - and certainly much wider than 1m. The dimensions you want are a bit of a problem. At 4m you want something that you don't want to be pruning to maintain the 1m width (unless you built a permanent scaffolding around it). The only thing that springs to mind is a conifer of some kind. But make sure it's going to stay within the 4m limit. An Irish yew (Taxus baccata 'Fastigiata') might fit the bill. Ultimately, it would grow somewhat higher than 4m but not in your lifetime. It does eventually widen out at the top but, again, this is a feature of maturity. What you would be looking at for at least the next ten to twenty years or so would be a very formal looking "punctuation mark". The leaves are very dark green and, unlike most conifers, are soft and feathery. The branches are very dense and upright. Small red berries are produced, rather than cones, and these tend to be hidden away in the foliage. Altogether, a highly desirable conifer. There is a photo of a pair of yews on this site. Unfortunately, the photo doesn't really do the tree justice. You have to see one in real life to appreciate the beauty of the foliage. There is also a golden variety but the few that I have seen growing tend to be quite yellow on the side exposed to the sun and green on the southern side. The timber itself is very attractive and is highly desirable to wood-turners. And you could make your own longbow. Here is a link that might be useful: http://www.hearstcastle.org/behind_scenes/plants/irish_yew.asp

OP is back ;-) I appreciate all the answers I've gotten and I realize that I didn't give you enough to work with. In the first picture, you see the spot. The distance between the house and the hedge is 5 feet and 9 inches. The window is facing north and there's a public walk/bike path on the other side of the hedge (so more or less right outside the window) as you can see in the second picture: The hedge is carpinus betulus and not particularly dense, especially not in the winter: The room (behind the window) is going to become our bedroom. The window sits rather low (knee-height) and it gets very dark here in the winter (from 3.30pm to 8.30am), so when the lights are on, we'd feel rather exposed :-( Blinds would be ok, but I'd also like some kind of plant outside the window that together with the hedge would make it less easy to see every little detail in our bedroom when the lights are on and the blinds open. I'm afraid I have no idea whether I have acidic soil... I'll look up the suggestions you've all given me, but please feel free to share your opinion now that you have more information.