Variety
A garden with a broad assortment of plants and arrangements can be a genuine delight. A variety of different plants can open new doors to contrast and beauty. After you have decided on a theme and style for your garden, try to select a variety of plant shapes and sizes that fit your theme and your site constraints. You don’t want to overdo it, though.
Keep your design simple, but remember that variety can be the spice of your garden.
On the same note, try to find creative garden uses for interesting terrain features. That rock outcrop may look like an eyesore, but with some imagination you can turn it into a pleasing garden. Sometimes it is better to enhance the unusual features of a landscape rather than remove them and start from scratch. Remember, though, that if you want to use that terrain feature to your advantage then don’t design something which covers it up or detracts from it.
Rooms
If you have a large site, you may want to break it up into rooms or compartments. The rooms in your house may have different styles and tones, and your garden can be like that as well. You may have a formal room, an informal room, a tea room, a solitude room. Fences and other structures can help enclose various rooms, but you can make rooms simply by having different themes in different parts of your site.
Deception
When designing gardens, you may want to create impressions that deceive: the small wooded patch in your backyard can give the appearance of a large wooded patch; a path that looks like a peaceful stroll to Eden may just lead to your pool filtration system. Hide air conditioning systems, electrical conduit boxes, and other eyesores with a few well-placed plants. By being creative, you can mask many of your site constraints and create a nice retreat. One useful deceptive technique involves slightly obscuring a view or path to instill a sense of curiosity in the viewer. A carefully placed plant or obstruction can entice garden visitors to explore further to see what may lay beyond.
Choose plants for all seasons
Many plants look good throughout the year. A deciduous shrub may have nice foliage and blooms during the growing season while in the winter it may have berries that attract birds. Some perennials look good even when dormant. Dead stalks and flowers can add a nice touch to the landscape during the bleak winter months.