Gardening in a depression

The most used part of my garden is also the hardest to work out what to do with. As you can see from the image below, it is banked on 3 sides very steeply, creating a depression of sorts.



South UK, zone 9, clay soil.

Mj Lacey wrote:The most used part of my garden is also the hardest to work out what to do with. As you can see from the image below, it is banked on 3 sides very steeply, creating a depression of sorts.



South UK, zone 9, clay soil.

Sorry, hit go before finishing! The bank on the south is essentially compacted subsoil and stones, as a flood defence against a river on that boundary, circa 60 meters away. It is significant overkill, it would only get that high in a cataclysmic event, but even so I am not able to remove it or change its height. Above the north side slope (facing south) is the driveway to the house and behind that a much steeper former hay meadow.

You can see whats here at the moment - just grasses on the slopes and an arbitrary former path that I have had to remove. I'm managing it now with a scythe and a strimer. The steps you see in the image are also being removed (they again, were arbitrarily placed there). The 'lawn' in the middle on the flat, I need to keep as a space for the children to play and for us to sit.

I am trying to fathom what I can do, that will suit such a significant slope, be manageable, bring in diversity, but also be aesthetically pleasing. Finding resources for inspiration and ideas is understandably very difficult - this is not a typical garden challenge.

Pitching here really to see if anyone has any ideas on how to create an abundant oasis, but also by sympathetic to the lines and shape that's here.

What a nice place!

The north facing slope provides a cool spot to sit in summer, the south facing side a warm one during the rest of the year.
You mentioned a river, so turning the center into a pond would probably be of little interest. Then again, since water is available a small water pump feeding a "spring" would provide lots of fun for children.

The simplest solution I can see for the north side would be to leave the grass. But it might also be a good spot for shade loving plants that don't like wet roots. (And a strip of sun loving plants at the top.)

Maybe even put a "ceiling" on the south facing side to prevent the warmth (IR radiation) from escaping upwards and wind from chilling.

It it possible you are in karst?
The depression looks like a doline.

PS: I didn't know UK has zone 9 climate, you sure about this?

R. Han wrote:It it possible you are in karst?
The depression looks like a doline.

PS: I didn't know UK has zone 9 climate, you sure about this?

No, we aren't - the bank has been built up, rather than fallen in. It is a flood defence, installed by the Environment Agency here in the UK. I own the land, must maintain it and can to an extent do as I wish with it. However, I cannot change the shape of the mound, or remove it.

Zone 9 depicted here: https://www.gardeningknowhow.com/planting-zones/uk-hardiness-zones.htm

Sebastian Köln wrote:What a nice place!

The north facing slope provides a cool spot to sit in summer, the south facing side a warm one during the rest of the year.
You mentioned a river, so turning the center into a pond would probably be of little interest. Then again, since water is available a small water pump feeding a "spring" would provide lots of fun for children.

The simplest solution I can see for the north side would be to leave the grass. But it might also be a good spot for shade loving plants that don't like wet roots. (And a strip of sun loving plants at the top.)

Maybe even put a "ceiling" on the south facing side to prevent the warmth (IR radiation) from escaping upwards and wind from chilling.

Thanks! Creative output is helped by restrictions, but this restriction is so specific, its hard to know where to start!

Its only about 1-1.2m tall - so its only shady early in the morning, or in the colder months. Through the summer it gets most of the southern / all of the western sun.

Interesting you should mention a pond; I have intentions to install a small pond on the top of the bank, directly in front of the image. It is about 20m back of grass, there is little other use for it. Given the slope, I may even be able to install a tap at the bottom, have a watering source for this part of the garden.

The top of the bank is a walkway, only 0.75m wide, so no scope to plant it directly - basically its a berm.

I've considered leaving it grass, and am open to that possibility, although would try to manage it to 'meadow' status. But from an aesthetic point of view, it would feel quite 'unbalanced with the planting on the south side - so I am trying to find a way to consider the visual impact here too.

If it's part of flood defenses the first thing is to check what you are allowed to do with it. digging a pond into it is probably not allowed. I guess it's to steep for a mower so if it were allowed I would terrace it and then grow anything I wanted (no deep roots) If you are not allowed to terrace and don't mind a lot of work a rockery would look lovely there.

Skandi Rogers wrote:If it's part of flood defenses the first thing is to check what you are allowed to do with it. digging a pond into it is probably not allowed. I guess it's to steep for a mower so if it were allowed I would terrace it and then grow anything I wanted (no deep roots) If you are not allowed to terrace and don't mind a lot of work a rockery would look lovely there.

Thanks. I'm actually fine to dig a pond where I'm proposing, I've checked. I can do what I like, so long as the top 30cm or so is open to be inspected and walked. Rockery I've not considered, that's an interesting idea.

That does look like a lovely spot.  You have sort of got an inverted "herb spiral" construction there!  However if the right hand bank gets a reasonable amount of sun and is sheltered from the morning sun, then you can consider more tender plants there.  It is often the damp roots (a slope will help keep them drained) and sharp temperature change as morning sun hits frosted leaves in the morning that causes the damage.  
The main disadvantage I see is the soil at the moment is not conducive to planting.  If you can get hold of some terracing materials, stones or rubble, to build some retaining walls and then back fill to give yourself some soil to plant into I think you'll be surprised what will do well there.  Maybe even citrus, or a scrambling grape vine.  Actually, you could just place more stones on the bank to capture the heat of the afternoon sun and plant at the base and let vines just scramble up the bank, together with tougher spreading ground covers like raspberries, strawberries, I'm sure there must be others.  Hardy kiwi, and roses are other sprawling possibilities.