When you are preparing your home for sale you must see it through the eyes of potential buyers. You want that initial impact to be a positive one, creating a desire that when they enter your home only increases.
Landscaping can bring a big impact for low cost, sometimes it requires removing things as opposed to adding. Don't be limited by your property lines look beyond those and see what your buyers see, how can you improve that view. We get used to seeing things and accept them rather than thinking about changing them. For example, a neighbor's shed may be unsightly, we live with it, a buyer sees it as an eyesore. But it can be shielded with fencing, trees or shrubs.
Look at your front and back yard as a canvas with three dimensions, a foreground, a background and the middle area in between. What are you going to paint on that canvas. I just had a customer remove a holly that was growing in front of his house by the bay window, it was large and growing irregularly blocking light and not adding anything to the home. Having removed it the Pennsylvania stone really shines and the whole front of the house is improved. Sometimes you dont have to totally remove something, but you can cut it back. Remember, home inspectors like plants and shrubs to be away from the walls of a home so the air can move freely around it.
Create depth and add dimension with your plantings, you need height as well in some areas like a work of art leads the eye you want plants and shrubs to lead the eye where you want it to go. You get more bang for your buck with shrubs and flowers than with hardscaping, so go to your local garden center and ask for advice. Also remember to create areas where people can sit and enjoy the yard, quiet zones, just as an interior has space for people to get away your garden needs "rooms" or places where you can sit quietly and enjoy the beauty you have created.
Like any improvement do these changes before you are ready to sell and enjoy the benefits yourself as well. There is nothing like working in the yard, not just clearing leaves and cutting grass but planting and planning flower beds, and then enjoying the work you hve done throughout the seasons.
