Every plant has a preference about its environment. Plant it in the wrong place and it will never reach its potential, no matter how much you may want it in your yard.
Sun
When choosing plants for your landscape, consider the availability of sunlight. Plants that love sun and heat will never be happy in full shade. Likewise, trees that prefer to be in the understory like dogwoods and redbuds will look a little sad planted in full sun. When surveying your yard, remember that afternoon sun is more intense than morning and that western-facing walls will radiate heat onto nearby plants. This may be beneficial for plants sensitive to frosts, but will be a problem for plants sensitive to heat.
Water
Plants also have a preference for water. Some like more, while some like less. You can alter this by adjusting irrigation to a certain extent, but be sure not to place a water-loving plant near a drought-loving plant. The two will never learn to be friends.
Disease issues
Avoid plants with known disease issues. Study up before investing in a new tree for your yard. Some species may do just fine in one area but be susceptible to all kinds of problems in your region. When in doubt, call your local Extension office. If a tree is prone to problems, no amount of TLC will keep it looking good. Avoid the problems and pick another plant.
Power lines and other headaches
If you get all the previously mentioned things right, don’t forget that your tree will grow! Before placing a tree, look up. Remember that utility companies have the authority to prune trees near power and telephone cables. Have the ground surveyed for buried pipes and cables as well before digging. (Call 811 to have lines identified.)
Be considerate of neighbors. Do not plant a tree directly on the property line. Even if your current neighbors love it, it can be a dispute in the future. Do not plant a tree that is going to shade someone’s vegetable garden or drop limbs on their car in a storm. Avoid trees like pecan and sycamore that are notorious for dropping limbs unless you can plant them safely away from cars and structures.