Landscaping: plant now, reap the benefits when you sell

One realtor in Washington, D.C., always assesses the landscaping around the house of a prospective client before deciding the approach to take in making a sale.

If the front yard is nondescript, he moves the prospective buyers right indoors and concentrates on selling the house.

If, on the other hand, the property is nicely landscaped - green lawns, appropriately sited trees, and flower beds - he parks across the street from the residence and lets the prospective buyers take in the more distant view. On these occasions he is selling a home, not just a house, and good first impressions go a long way toward clinching the deal. In turn, good landscaping ensures that those first impressions are favorable.

Effective landscaping does two things for a house going onto the market: it increases the value of the house, and it speeds up the sale.

Recently, Scotts, the lawn seed and fertilizer company, commissioned an independent research organization to evaluate the importance of landscaping to the real estate industry. Realtors in Chicago, Denver, and northern New Jersey were asked: How important is the landscaping when it comes time to sell a house?

Attractive flowers, shrubs, and trees, along with a good-looking lawn, would add about 6 percent to the value of a house, the realtors estimated. Just as important, and perhaps even more so in their eyes, an attractive yard ''helps a house sell more quickly than otherwise.''

The United States Forest Service, reporting on another study, confirmed these findings, as the scientists concluded: ''Trees may enhance the value of a property by as much as 20 percent, with an average increase ranging from 5 to 10 percent.''

Not long ago a friend of mine invested in some professional landscaping for his Greater Boston house, and his reasoning made a lot of sense. ''Why wait until you're going to sell before you do up the place?'' he said. ''Sure, I expect to get more money for the house when it eventually comes time to sell. But meanwhile, we're enjoying the benefits. It (the house) is a nicer place to live in right now.''

The American Association of Nurserymen emphasizes that point as well: ''The same qualities that impress a potential buyer enrich the quality of life for those living there now - beauty, cleaner air, privacy, quietness, recreation, and more.''

Meanwhile, fall is frequently the most appropriate time for setting out many trees and shrubs. The weeks ahead provide plenty of time to begin upgrading the landscape around your house.

''Most containerized or balled or burlapped plants can be planted at this time of year,'' according to George Good, professor of floraculture at Cornell University,'' who lists spruce, pine, juniper, honey locust, maple, flowering crab apple, lilac, and linden as among the many species that can go in at this time. Yew, forsythia, English ivy, and rhododendron are others that are suited to fall planting.

At a Long Island test site many species were planted out in late August, September, October, and November of l980, and again in May and June of l981.

All these plants were evaluated through the 1983 growing season. Only among the plants set out in late November was there any winter kill at all.

For the rest, the fall-planted specimens did every bit as well, and in some cases better, than those planted in the spring.

The conditions that make for successful fall planting are:

* The soil remains warm after the hot summer months, yet air temperatures cool down. This condition stimulates rapid root growth, important if the plant is to become established before winter.

* Rainfall is generally reliable during this period while daytime air temperatures cool down so that the plant is not required to get rid of excess heat by evaporating moisture from its leaves.