I am sure there could be many views on the best method of doing this!

You don't mention what the existing surface is so I am going to assume it is soil or lawn!

The first task is to get rid of the topsoil/ turf!

Cut around the perimeter with a spade or edging tool the remove the the topsoil / turf to a depth of around 4"-5" (100-125m).

Place a layer of sand around 2"(50m) thick over the area this will prevent any loose stones puncturing your weed membrane.

It will also allow you to level the area, meaning you will have a uniform depth of gravel ( sand is normally cheaper than decorative gravel)

Lay out the membrane on top of the sand.

The next task is to lay the bricks around the perimeter!

You do not mention what diameter you plan on making your circle so I will suggest two practicle alternatives for setting out the bricks!

For a diameter of less than 12ft(4m) you will need a timber lath roughly 2"x1"(50x25mm) by 6ft(2m) and a steel pin to act as a fulcrum.

Drive the pin into the centre of the circle,drill a hole in the timber to suit the diameter of the steel pin.
Fix the timber to the pin like the finger on a clock this will act as a template ( trammel) for laying the bricks.

If the circle is larger than the sizes mentioned above tie a length of cord to the pin in lieu of the timber.

Either tie a knot in the cord, or tie a nail on to the cord to the required radius of the circle.

You are now ready to lay the bricks!

Mix a batch of sand and cement to form the bed for the bricks BUT DO NOT ADD WATER!

A mix of about six to one should be OK

Place the first brick on the the sand cement bed at the predetermined internal radius and level it up both length and width!

With brick two (and subsequent bricks) lay it / them so that the edge touches the previous brick.

Note;this will create a ' Vee' joint along the length of the brick of a width that will vary subject to the diameter of the circle i.e. the bigger the circle diameter the narrower the joint.

Carry on laying subsequent bricks, checking each one with the timber trammel or cord.

Note;you may find it better to firstly roughly lay the bricks ot dry and adjust the diameter of the circle slightly to ensure you get complete bricks around the perimeter.

If you don't you might find you either have to cut one or two bricks to make them fit, or open up the joints slightly to close the circle.

Once the bricks are laid as you want them leave them to set for a couple of days,the natural moisture in the sand and the atmosphere should make the cement set.

If you want to speed up this process use your watering can to sprinkle the bricks with clean water. The potential trouble with doing this is the bricks can become smeared with cement which is virtually impossible to remove once it has dried.

The next task is to form your central mosaic.

This is done in basically the same manner all that is required is to mark your trammel or knot your cord to suit the required diameter of the central mosaic, and lay you bricks/ mosaic

Once all the brickwork is complete and the cement has set you fill the sunken you have formed with gravel.

The only thing that is required now is to fill the joints in the brickwork.

To do this again make a dry mix of sand and cement but this time make it a bit stronger say two or three parts sand to one part cement.

Trickle this mix into the joints and brush the surplus off to leave a flush joint.

This mix should harden off within a couple of days subject to the weather.

I hope this info helps!

Best of luck....Tg

What a wonderfully concise answer Tee Gee! It's not my question, neither am I about to create a herb wheel, but I almost wish I was, having read your instructions! :o)

I enjoyed this question and a really good answer.
I did something similar about eight years ago (without the mosaic) and used sleepers for my edging as it was oblong in shape. I used a double layer of membrane instead of the sand and a large size gravel which stop cats using it. In all that time I have not had one weed in it and all I do is rake it over once a year.

Fantastic! I agree, Nariz - it makes me want to do something similar! I could visualise every stage of the construction, Teegee.

wow fab answer. how nice of u to take so much time to explain the process :-)

Thank you for your detailed answer, Nariz, I'm sure I can't go wrong using your guidelines, and many thanks to DRC, Melchi and Gerber for your comments, too. I hope to get this finished before the winter so I'll let you know how I get on.