When I set up my Container Garden with lots of ideas from Goy I was lucky, the contractor went to another town
especially to get builders' gravel. Its larger, and looks
better. If you could locate some and put it on the surface
you would be happier.

20mm sounds large to me. What size did you want originally Sonot? What is it about it that you don't like? I'm sure it will look better when its planted up, its bound to look like a desert at first. I hope you don't wear high heels if you're having gravel paths though!

You could mix in a smaller size, and some larger stones. That would look more natural. What's the gravel?

The larger stones are better for drainage than the smaller ones, so mixing sizes in as others have said would work a treat.

I prefer the idea of Worthy1. Mix in some 10mm and 16mm grit and include a few large rocks in the bed. One size gravel is boring.

One of the benefits of larger sized gravel is that cats are not likely to use it as a toilet. Smaller sized gravel can be a cat magnet.

I would recommend planting some low growing evergreen perennial plants or heathers through the gravel.

Gravel on its own is boring but with the addition of a few perennials/small shrubs it can look lovely

Here are some I've created in the past

http://www.flickr.com/photos/31559373@N00/8704796974/

http://www.flickr.com/photos/31559373@N00/2778538917/

http://www.flickr.com/photos/31559373@N00/3380217786/

and another where I supplied the plants but the customer designed and built it

http://www.flickr.com/photos/31559373@N00/3528800857/

About 10 years ago I laid a side garden with this size gravel as the cats will not use it as a toilet like they do with smaller gravel and it is easier to keep looking good as it does not shift about as much or get covered in muck as small gravel can.
I love mine and I think you will learn to love it too - try planting it with interesting plants and or pots to add interest through colour and structure, start collecting coloured stones to sit amongst it, such as a piece of pink sparkly granite so it looks great in the sun and rain. Also give some thought to the path which can add more interest such as coloured slate one.

If you click on the Letter G at the bottom of the page, select Gravel Garden Ideas there are in excess of 300 pictures. Plenty of inspiration to be had.

Thank you all for your help. I will look again at the photos, but realize now that me and Beth Chatto have very little in common!!
The gravel is Forest of Dean pink. I already purchased some grasses last weekend whilst in Surrey at Longacres as they do have a good selection. My intention was a white and silver and grasses sort of thing with some splashes of pale pink and lavender. Lots of things that would self seed. Will they be able to find their way through 2inches of 20mm to the compost and grit I laid down?
I am not very artistic and struggle to picture the finished product. I have a friend (who lives many miles away unfortunately) who can artfully place rocks etc. to make an impact but if I attempt that it ends up looking like I have just thrown them from a distance! Spent a sleepless night last night worrying about it, as at the moment it looks like a builders yard!

The moist and warm atmosphere of gravel is an ideal place for seed to germinate - too well as you may find out!

I do so sympathise Notsogreen - I can't visualise either and its a real pain - can't see if its right until I've done it and then its too late. Have you tried any of the garden planning websites where you can experiment? Your colour scheme sounds lovely.