Monday, 2 March 2015

Limestone in Landscaping: what is available? A comprehensive Guide

Limestone Quarry


Limestone is a natural product that is in plentiful supply in Western Australia, thanks to the large amount of limestone deposits available around the state. Limestone is quarried both as limestone blocks for use in construction, and also as crushed limestone which has a great many uses. Crushed limestone can be used on its own in landscaping, spread and compacted to create a usable surface for paths, and is readily available at landscape yards. 
Crushed limestone road

Crushed limestone can also be mixed with a small amount of concrete and water, and used to mould reconstituted limestone blocks, or used as liquidlimestone, also known as poured limestone. Liquid limestone is used for paths, driveways and patios in landscaping.
Liquid limestone patio

Reconstituted limestone blocks hold many advantages over the natural limestone blocks that are quarried straight from the ground. Reconstituted limestone blocks are stronger and denser than natural limestone, making them the perfect choice for retaining walls.
1 metre limestone blocks for retaining

 Because of the addition of concrete in the manufacturing process, reconstituted limestone blocks don’t discolour and go black with age, as does natural limestone blocks. 


Because reconstituted limestone is manufactured, the blocks can be made into any size, and can include features such as bevelled edges.
limestone block with bevelled face

Reconstituted limestone can have a pigment added during the manufacturing process, so while it still maintains the strength and texture of the limestone, its naturally light colour makes it the perfect medium to take on a different colour. 
limestone blocks with coloured pigment

As the blocks don’t have to be quarried in the same way natural limestone blocks do, it also means reconstituted limestone blocks are cheaper to supply. Manufacturing reconstituted limestone blocks means that there is no waste product, as it is the loose limestone that is used. 

Due to limestone being a natural product, and also due to the different manufacturers, there is some variation in the colour of reconstituted limestone blocks. They can range from cream to off white.

Reconstituted limestone can also be moulded into pavers providing an easy to install outdoor limestone area. Liquid limestone has the benefit over limestone paving that it doesn’t have joins and gaps for weeds to grow through or for ants to create their burrows.

Liquid limestone is installed much like poured concrete, poured into form work and screeded. Control joints are added during the curing process, and different patterns can be carved into the surface.
Liquid limestone driveway

When considering using limestone blocks in landscaping for retaining walls, garden edging, piers, planter boxes, built in barbecues, raised garden beds, and walls, there are a few variations in both product and installation. As mentioned, reconstituted limestone blocks can vary in colour, because of the manufacturing process of the natural limestone, and also you can choose a block that has had a pigment added to create an earthier colour. Also, as mentioned, limestone blocks can either have all flat faces, or can be manufactured with a bevelled face or top. Consider the size of the blocks and what is suitable for your limestone project, though a professional limestone installer such as Perth Trade Centre will be able to advise what block size might be suitable. Different sized blocks can be used in a limestone wall for a more unique feature. The mortar joins of the limestone block work can vary, depending on installers and tools used, and the desired finish. For information on sealing limestone blocks after installation, click here.

It is also possible to transform certain walls that are not limestone, by spraying them with spray on limestone. This process coats a wall, such as a brick wall, with liquid limestone made to a ratio specifically for spray on application, then the wall is hand carved at the appropriate time during the curing process.
Spray-on Limestone being hand carved


Limestone in any form, can add an elegant, classic aspect to any landscaping project, and has many benefits well worth considering.