Raised beds and existing plants

We moved into a new build a year ago and had a patio and beds cut in the summer. We are surrounded by a 4 foot retaining wall on two sides which then had a 5 foot fence on top.
In a rush I planted plants I had brought and also some we had rescued from the developers who were ripping them up. Today we went to start moving them to find that at about one and a half spades depth is concrete up to two feet from the retaining wall.
The back bed is deep and we planted four Himilayan birch trees, they miss the concrete. And lots of climbers.
Do I need to put in raised beds; I assume nothing will grow well and it could hold water. I had planted small lilac tree, snowball tree, silk tassel, Chinese creeper, honey suckle, amandii, solomens seal, bleeding heart, lots of ferns. Will they survive a move in mid spring? Lots of bulbs too.
Funnily enough we had drainage put in and I never saw the concrete when it was being laid.
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Feeling rather depressed about it. Would I need to dig up the birch if they were to be in the raised beds?
How much space is there between the front of the beds and the wall? ie how deep are the beds? If they are a decent size then losing 2 foot of them is not a catastrophe. But if your beds are 3 foot deep/wide then it is.
The one along the left hand side is only about 3 feet deep.
The walls foundations shouldn't over sail the width of the wall at all let alone by 2 feet? You can cut/dig the concrete back as long as you don't undercut the wall at all
I think it is strange that we didn't notice it before as it isn't that deep. But I think it is a lot of concrete. It is like a slab and goes up the length of the wall for about four metres.
I don't think all is lost. On the basis you have nothing to lose I would try a mix of perennials and ground cover plants. Just steer clear of big shrubs. The smaller heels would be fine. A spade and a half is about 12-15 inches soi think they would be ok. At least your trees have a clear root run.
If it all doesn't work out, you have the option of trying to remove some of the concrete.
Why don't you make your borders/beds in the middle of the garden and grow grass up to the fences. That would be the easiest of options.
Thing is the wall with the fence on top looks terribly imposing and boring which is why I was going for tall shrubs and climbers and the garden isn't large and we need the lawn for a small child to play on. Plus the houses above look down on us.
Would the plants survive transplanting and would the trees survive being dug up and replanted?
I have someone coming round Monday to quote.