here's a free garden design programme to download and try rainwater Link: http://www.bbc.co.uk/gardening/htbg2/virtual_garde
n/offline/garden_setup.exe
Professional garden designers are moving more and more towards CAD for drafting their plans - but many (myself included) still spend time working at a drawing board as well, especially for the early stages when you're roughing out the basics of a project. The programs we tend to use are Vectorworks, AutoCAD and TurboCAD but they all cost a fair bit and have a steep learning curve.
So, a drawing board may actually be the best place for you to start - but if you really want to use the computer a free option for mucking about with ideas is Google's Sketchup. This is a simple 3D drawing system that lets you build models of gardens quickly and easily - you can also add dimensions and other details to the plan to help you do the construction yourself, and there are video tutorials on their website so it's relatively easy to learn.
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