FredAt wrote:
Hello All,

I am in the process of planning a raised garden behind my new house.
The raised area is around 6m long and 7m wide ending in a tall
embankment. Half of it gets strong sunshine till around 14:00h during
the summer and is then in the shade. The other half, including the
embankment, remains exposed to sunshine till late in the evening
during the summer months.


Put your fruit trees and productive vegetables that need full sun in the
latter half if you can manage. You can get quite a range of flowers,
shrubs, and veges that will do with half sun in the other area.

I will be building walls to raise the area to be able to walk out of
the French windows at the back of my house. I need to backfill and
then put top soil to a height of 1.2m. I have several questions

a. How much top soil, i.e. depth, should I put in. By and large what
we will have there will be a mixture of herbs, leek, cabbages,
carrots etc. Some flowers a couple of apple trees and perhaps a
cherry tree.

Most of your veges will do fine in 40cm of soil, many are shallow rooted and
20cm will do but to have the option of rotating them make it all the same.
It depends on the cost whether it is worth using cheaper "clean fill"
underneath and garden loam on top or all loam. Your trees will do better if
the soil is the full 1.2 m or deeper Always remember that any earthwork,
especially major works, must be planned with drainage in mind. You need to
know where the ground water runs now and what your fill will do to that
flow. You don't want to do what I have seen done, where the first time
heavy rain fell all the water ran straight to the back door and into the
house.


b. What do I need to know about the type of top soil to use - I live
in Luxembourg. We get around 900mm of rain per year and the soil is
very well drained.


The best garden loam that you can afford. See above.

c. How can I put the embankment to good use - it rises to a height of
around 12m at an angle of around 25° (quite steep) and is currently
covered in brambles and the like

I'd much appreciate any help

This is quite steep for any regular cultivation. If you wanted to have
walks and made gardens there you would probably have to terrace it. If you
don't want to go there then replace the brambles with shrubs, perenial
flowers, ground cover etc that will be low maintanance and help to stabilise
the bank. How does the water run off this bank now?

A trip to the local library and some study of books on garden design and
layout would be well worth the time.

David