Posted: 29/08/2014 at 00:21
Have a look at smallblueprinter, its free for the first few days which gave me just enough time to design my garden.
If you don't want to pay for the full package then first sketch/design your garden on paper and when your happy download the software. This way you will be able to allow time to get your head around how it works, and complete your plan before the free version expires.
Heres the design I did for my garden using smallblueprinter