What to grow on extreme sandy soil?

Perhaps you could look at desert plants Sian? Most suggestions have already been spoken about but one I didn't see was Valerian. The only other idea I have is raised beds to 2ft or more.

 

I can think of two bulbs that should do well for you Sian.... Tulips and Iris.

With the Iris go for Iris x Hollandica. They're much bigger bulbs and flowers than normal Dutch Iris and come in a fantastic range of colours. I grow mine in a mix of compost, sand and gravel.

In your sandy soil both would get the summer baking they need to build up reserves for the next year.

 

Armandii, on the Isle of Man it runs riot there in red, pink and white. It definitely grows well in a coastal position so should be happy with sand.

 

Thank you for taking the time for this answer, @ARMANDII . Your experience in this sort of situation is invaluable! I will do my best to respond...

yes, the herb garden does well. Alarmingly, that area has even more drainage than the rest of the lower half of the garden, as it's the site of a second building. (You may remember photos of a cellar I nearly fell down when I uncovered it, as I was digging a planting hole for my Kilmarnock willow). If I know I need a plant to prevent erosion, etc, it's a cutting from one of my herbs that I reach for.

Thank you! I have gardened for many years. My experience here makes me yearn for the 15cm flinty soil on top of solid chalk, that I had in the Chilterns! Yes, we needed a crowbar to make planting holes for trees, and go up 2 rootstock-types to get any growth, but at least they did grow...
We have made the sad decision to give up on apple trees here. Since we moved, 2 established trees (at least 15-20 years old, judging by other trees' rate of growth) have died, along with 4 trees we have planted in deep planting holes filled with rich compost.

I have probably bored you all silly, trying to describe the soil, and layout of the garden! The slope is the hardest - I'm not good at judging gradient. Does it help to say that when an estate car parked on the flattest part of the slope, with the handbrake left off, started to roll away, I caught up with it within 20 metres and only just managed to run fast enough to jump in, to stop it....?

I only try to grow the plants that I love in the lower half of the garden. Apart from one small strip next to the garage, I have not really tried to grow anything in the ground in the upper half of the garden. My attention has been focused on working on improving the soil in the already improved flower beds in the lower area, mainly around the house. These benefit from a little shelter from the wood to the east of us, and some from the house itself.
Ironically, our neighbours envy us our unbroken view across the valley! I have tried to explain to them the hazards of this beautiful view. Losing a tall conifer 6 years ago, and our drive gate this spring, has brought home the wind-tunnel effect...
The garden is maybe 50 metres long? The slope is about the same down 4/5ths, and then gets very steep (overturning lawmower steep) in the bottom 1/5th. The effectively-a-bungalow house is just under 1/2 way down, and the roof is about level with the road. The tops of established oak trees level with the bottom of the garden are level with the road above us. So planting trees at the bottom as windbreaks for the garden would require about 50 years' growth, before they provided shelter.

This is the bit that is making me despair - planted trees just sit there! They don't put on any growth, then some just die, after 5 years... We have a few trees that has put on some growth. Our infamous Aldi "sour cherry" tree (very nice plums they are too!) has grown from a skiny 2-year old whip to a a 3 metre tree, with a good shape. But it was planted in the centre of an established bed, which was full of brambles and birch growths when we moved in. We cleared the undergrowth, put a cubic metre of compost on top, dug a large planting hole and filled with more compost. It is also quite near the 2nd septic tank ...
Basically, the only trees that have grown are either protected by buildings, or are in existing beds where the soil has been worked for decades. All these locations are now planted.
I would like to speak to the previous owners who took down the established tree (probably oak or poplar) that was just over half-way up the garden. The stump was about 60-70cm across, but has now rotted out. The loss of this shelter tree is probably why established trees at the top of the garden are now starting to fail. That, and climate change?

 

This is what I am trying to do with the "grass" at the top third of the garden. It is cut just once in the growing season, around July, but as you could see in the photo, very little grows anyway. Wildflowers struggle - I think it is safe to say I don't need to source yellow rattle seeds! Maybe I should stop pulling out the broom plants from the grass areas, and see if they provide enough shelter for wildflowers to establish...

 

I love most plants, @Sheal , but Valerian is an exception. Memories of my wedding dress being soaked on the way to the church, by valerian overgrowing the path to the car? But yes, it would add some colour... I will lift some plants from home, when I'm next in the UK, later this month. Deadheading would definitely be done, though, @ARMANDII to prevent any invasion!

 

Iris - now I haven't tried them much. I have an iris tuber that a neighbour had thrown onto the derelict land opposite his house, that I rescued. It has been in the garden for a couple of years now. It has leaves, but still no flowers. I realised from a GW program earlier this year that I'd accidentally covered it with mulch, so I've cleared the tubers, raised them higher - maybe I will have flowers next year?!
Tulips can survive, but they struggle with the summer droughts, I find. So they do well in the improved beds, but not in the basic bed at the top of the garden. I will persevere with them, though, as hubby loves them!

 

Sea buckthorn - I've tried to avoid thorny plants, as an act of self-preservation... but this looks interesting, and something that I can eat too?!
Tamarix - my parents had the some of the first plants in the midlands. Many years ago, Wyevale gardeners used to do the autumn prune of hedges, fruit trees etc, in return for the cuttings from the tamarix... I think only one tree now survives. Not sure it would cope with our winters though...?
Chitalpa tashkentis - very interesting. Is it available? In the UK? Europe? Invasive? (afraid of introducing invasive non-native species...)
Griselinia littoralis - This looks very much like the hedges that we have - we call it soft laurel, but I think it's this? Slightly sweet smell when cut? Stems/branches surprisingly brittle and soft?

 

I'm off to google these three plants right away!! ...and back...
Callestemons - they look lovely, but I need H5 or H6 plants, so an H3 hardiness would not cope with our winters Grevilleas has the same hardiness problem.
There are 9 Salvias that might do the trick - liking the look of lavendulifolia and Hot Lips so far!

 

The soil here is sandy......close to the beach after all.
A garden of two parts.....
The front has poorer soil; the back used to be a small holding and lots of top soil was brought in so excellent there.
However, over the years I have added tons of manure, mushroom compost, seaweed and the like.
The secret is to establish plants and then they will tend to look after themselves..... viz., adding manures etc at planting time and keeping plants well watered until established

Overlooking the beach I have friends who have nothing but sand around their chalets yet have produced charming and productive little gardens. I have even helped in making one of the gardens myself ...it can be done, is being done and many of the plants I grow here have been successfully added there

 

name should be tashkentensis. Non invasive as far as I know, I got mine from a Cornish plantsman a few years ago, still waiting for flowers though. More info here Chitalpa tashkentensis 'Pink Dawn'
Some UK suppliers here Suppliers of x Chitalpa tashkentensis | Plant finder & selector/RHS Gardening
Some of the species Buddleja such as crispa might cope coming from the mountains of Asia will take the cold and long dry periods in poor soil. Unfortunately not necessarily easy to find.

 

What about agapanthus?