"Landscaping is one of the most important things you can do to a house to make it salable," said Dennis Byron of Byron and Associates in Los Gatos. "I would say that most homes are sold before the client ever walks through the door. You don't get a second chance at first impressions. If the home doesn't look good from the front, it will be an uphill battle to sell it from the inside."

Byron, who serves as chairman of the Los Gatos­Saratoga District of Silicon Valley Association of Realtors, recommends adding color to the exterior of the house to perk up the landscaping.

"Get colorful flowers to decorate the walk. Put pots with color on the porch. A rich green lawn area stands out in the eyes of the buyer," Byron said. "As for trends in landscaping, fountains and waterscapes are very popular today. The sound of water is a perfect white noise to soothe the soul and calm the nerves."

Realtor John Leslie of Alain Pinel Realtors in Los Gatos believes landscaping can mean as much as 5 percent added value or a 5 percent decrease in the selling price.

"A presence or lack of harmonious landscaping can make or detract from any property on the market. Agents tell other agents how a property looks, and curb appeal is number one," Leslie said.

Common problems when it comes to resale include a new home that lacks any landscaping or an older home that is overgrown. People are often reluctant to spend money on landscaping as they prepare to put their homes on the market, but Leslie thinks it makes a difference when sellers stage their front and back yards with the same detail as they do when staging the interior of their homes.

"I always encourage sellers to spend money on the total cleanup of their yards. Hire a gardener and get the plants and shrubs looking neat and healthy. Haul away yard debris and old dead or dying shrubs. Add flowers and ground cover or bark to all the flowerbeds. All these steps give the property great curb appeal," Leslie said.

Buyers complain the most about ugly lawns and broken watering systems. "If there is time and enough money in the budget, make sure there is a functioning sprinkler system and an established sod lawn," Leslie said.

In order to entice buyers, it's important to give them a great first impression, said Realtor John W. King of Alhouse King Realty.

"One of the easiest and most effective ways to improve the value of a home is by improving the curb and yard appeal of the home with landscaping. You don't have to re-landscape the entire yard, just spruce it up by cleaning it up, planting flowers, re-sodding the grass and refinishing the deck," King said.

Realtor Steve Bellumori agrees that the first appearance of a home is always very important and contributes to the response a home will receive once it's placed on the market. There are some basic guidelines that hold true since landscaping comes in all categories and sizes depending upon the price point of the home for sale and the size of the lot as well.

"Regardless of size or price point, the landscaping should be an asset to the property and at minimum receive the same fine-tuning that the interior or exterior of a home goes through prior to going on the market," Bellumori said.

For homes that are professionally cared for, there is rarely an issue of the home needing much work other than possibly dressing out the borders and adding color when appropriate. For homes not professionally maintained, Bellumori advises homeowners to prune plants, shrubs and trees and trim the lawn.

Adding flowers or colorful plants to highlight certain areas of the yard can pull the eye away from problem areas. All leaves and other debris must be removed. If the owner has enough advance time prior to placing a home on the market, Bellumori suggests fertilizing or aerating the lawn so that it is green and fresh-looking. Sometimes it is necessary to install new sod.

"Perceptions of good value are always at the root of how a home will perform on the market. The condition of any home or any landscaping can obviously be offset by price positioning of the home, but we've found over the years that the better presented a home is in terms of visual impact, the better the home performs on the market," Bellumori said.

Keeping a yard in shape has some other benefits for homeowners as well. A well-manicured lawn, colorful flowers and attractive landscaping provide enjoyment on a daily basis and create goodwill with the neighbors, too. When it's time to sell, landscaping provides added value that can translate into a better return on an initial investment.