Take a photo of your house, lay tracing paper over it, then try drawing a composition of different plant forms in front of it. Think about accentuating your entry, while also framing your house overall. Mix different forms, plus layer them (2-3 rows of plants is much more interesting than one). Click here to see an example.
Below is a simple tutorial of how to draw a tree, so you can focus on designing, rather than worrying about your drawing skills (anyone can draw a tree, really). I also have a slightly different format of this graphic tutorial available for purchase as a digital file here or a hard copy here.