I am looking for a solution to our privacy problem with our neighbours in our back garden.
We live on a hill and our back garden is lower than our neighbours. This was not a problem before but we have now extended our house and taken down our conifers. The fence between us and our neighbours is over 25 years old and is a wooden four foot high fence. Because they are higher than us we feel like we are in a goldfish bowl and would like to get some privacy. The neighbours are not planning to replace the fence and don't seem to mind the lack of privacy on both sides.
In our garden we have a retaining wall, the top of which ends at the bottom of their fence. At the top of our wall there is a very thin area in our garden that I can plant in. I would like to plant something that will grow about five or six feet high that would give us privacy. However, it cannot be a tree or shrub because there won't be room for large roots. I was thinking of planting sunflowers and some tall border plants. I may be able to push some canes into the ground and attach netting to try to grow sweet peas. Can anyone suggest any other options? We cannot and won't attach anything to the neighbour's fence as it is so brittle. Thank you.