These troughs are fairly easy to make and look really fantastic when planted up with alpine plants.

They are made from 'Hypertufa' - this is a concrete mixture made up from:

1 part of sharp sand, 1 part cement and 2 parts of peat or peat substitute ( e.g.. Coconut fibre).

What you will need:

You will need to make 2 boxes from thin plywood, one just slightly larger than the other so that there is a 2" gap all round between the two, when one is placed inside the other. The size of the larger box depends on what size you want your finished trough to be.

What to do:

Mix together the 'Hypertufa' using measures above. Ensure that it is thoroughly mixed up while dry, then add enough water, a bit at a time, to give a fairly wet mix. It should be wet enough to stick to your trowel and not pour off when tilted sideways.

Cut a piece of the wire mesh to fit the bottom of the larger box. Place a 1" layer of the 'Hypertufa' mixture in the bottom of the larger box, place the wire mesh on top of this layer and then add another 1" layer of the mixture.

Cut four lengths of the dowel to 2" in length and push these down into the mixture. These will act as supports for the smaller box and will also make the drainage holes in your trough.

Place the smaller box on the supports, ensuring that the gap between the 2 boxes is equal all the way around.

Cut another piece of the wire mesh, this needs to be long enough to go around the circumference of the boxes and about 1/2" below the finished height of the trough. Bend the mesh to fit in the centre of the gap between the two boxes. Ensure that it is roughly in the centre of the gap when you have finished forming it.

Now fill in the gap between the boxes using the 'Hypertufa' mixture, ensuring that the smaller box does not get moved out of place. It may help if a couple of bricks or something heavy is placed inside the smaller box to prevent it from moving about too much. Tap the sides of the boxes occasionally to release any air bubbles that may have got trapped and smooth of the top edge.

Now all you have to do is leave the boxes in place for about a week until the cement has set.

After this time you can carefully remove the boxes and very carefully knock out the wooden dowels. If they prove difficult to remove don't be tempted to hit them harder, it will only crack your trough, leave them in place until the cement has fully set and then drill them out.

Scrape the corners and top edges of the trough slightly to give a rounded effect. Leave for another week to fully harden before filling with a gritty compost and planting up.