Here is a link to an article about Free Landscape Software with 6 different programs. Here is another article listing 9 Free Landscape Programs. Many of these tend to be "free trial" versions. I haven't tried any of these, though I have used such a landscape program. There is a learning curve to get through. And, you may be limited in plant, hardscape or deck selection. An over-time-view that shows the growth of plants can be helpful. Read through the descriptions and pick one program to try. There should be a HELP guide available, but some of these may be better than others. If the first one doesn't work out, try another.

Due to the limitations on plant selection in these programs, you should always pay attention to plant info tags when shopping. Remember that dwarf only means smaller than the species, and the small plant at the nursery may grow quite large. If a plant will mature to 4 feet wide it needs a bed that is 4 feet wide or greater. Otherwise, it may block a pathway or lean away from a building or fence. Good luck.

Mindshift this is awesome-thank you!!

When you use software, pay attention to size, particularly grown size. There are some programs that will let you size your tulips larger than your oak trees. You can make lovely mock-ups of stuff you'll never achieve in real life.