Do yourself a favor and take care of some of your garden planting tasks this fall instead of delaying them until next spring. Right now is an excellent time to plant trees and shrubs.

In the spring of the year, after the long, dismal winter, most gardeners have no trouble being motivated to get out into the garden and plant. The problem at that time of year is too much to do. In addition to planting trees and shrubs, we have annual flowers and vegetable gardens to get in, as well as pruning, spraying and general garden cleanup. Fall is usually a more leisurely time in the garden and is an excellent time to plant nursery stock.Other advantages of fall planting include drier soils. If you had to wait for your soil to dry out in the spring or you ended up digging in sticky, wet soil, you'll appreciate this benefit. The warm soil temperatures enable the plants to get off to a good start. Roots grow quickly in the warm temperatures, and you'll get a good jump on the spring season if you get them in right now.

Perennials can be planted any time from late summer until the ground freezes. However, when soil (not air temperatures) gets below 40 degrees the root growth slows. This generally happens sometime in late November. Since it takes a minimum of three or four weeks for the plant root systems to establish themselves, don't wait too long before getting the plants into the garden.

Proper planting techniques are needed to ensure the success of your trees. The old saying "Don't put a $10 tree in a $1 hole" should be adjusted for inflation and probably should read "Don't put a $100 tree in a $10 hole." The principle is still the same. Always dig a planting hole several times the size of the pot that you are going to put in. Soil amendments are not usually a good idea. Studies have shown that root systems of trees planted in highly amended soils seldom get out into native soils. Therefore they never flourish or develop a good healthy root system.

Unless the soil is extremely poor, don't add soil amendments. If you feel you must add something to soil, choose the soil amendment very carefully. Never use peat moss on heavy clay soils. One reason trees fail to grow on heavy clay soil is because of poor drainage. Poor drainage translates into poor aeration - the oxygen does not get down to the roots of the tree.

One of the few materials that holds water better than heavy clay soil is peat moss. For heavy clay soils, choose a coarse, composted, bark product with chunks a quarter of an inch or more in size. Peat moss is fine for light, sandy soils, but is best tilled into the entire planting area rather than mixed in the backfill. Never place material in the holes in layers, that is, a layer of soil, a layer of sand, a layer of peat moss. This is a surefire way to ensure the death of your tree.

Those gardeners with problem soils should check the drainage. Dig the hole, fill it with water, and let the water disappear. Fill it up one more time and if the water doesn't drain away overnight, your tree has little or no chance of surviving without major changes in the planting area.

Be sure to completely remove the pot when planting a tree. Plastic pots should be cut down and the root ball lifted out and placed in the hole. "Plantable" paper pots aren't. Place them in the soil, and then carefully cut away all that you possibly can. You may have to leave the section underneath the root ball. On ball and burlap trees, cut the twine and remove it and cut away as much of the burlap as possible.

Each year I see hundreds of trees that don't make it just because of improper planting techniques. When planting a tree, put the backfill around the root ball and water as you go. After you have planted the tree, water only as needed. Check the soil several inches under the surface before applying more water. Over-watering destroys trees because it keeps the oxygen away from the roots.

Staking trees is generally not recommended. Only in the case of a large tree should you even consider staking. Staked trees tend to grow taller, but are weaker and will ultimately have greater problems when the stakes are removed.

Transplanting trees and shrubs is another frequent concern. Is now the time to transplant tree shrubs? In general, leaf fall is one of the most stressful times for a tree. I would recommend delaying until spring any attempts to transplant woody plants of any size. Better still, consider the cost of that tree in terms of hours of digging and the possibility of an injured back and the price of a doctor's visit. In most cases, it makes the price of a new tree seem somewhat less.

In addition to the horticultural reasons for planting trees and shrubs in the fall, there are two other excellent reasons. First, nurseries are not as busy now as they are on a Saturday afternoon in May. They have more time to discuss changes in the landscape and recommend plants that do well in your garden. And second, nurserymen also do not want to go to the trouble and expense of carrying over trees and shrubs through the winter. Trees planted with an established root system in the soil will survive winter with no problems. Those in pots are a different matter. They require special care to get them through the winter. For this reason you can generally save some money by visiting your nursery now.

Make your garden even better next year by planting trees and shrubs this fall.

- Join me this Saturday on the KSL Greenhouse Show from 7-10 a.m. My guest will be Ed Platt, president of the Utah Nurserymen. We'll be talking about fall planting.

- The Utah Orchid Society will present "A Cascade of Colors" at Trolley Square Oct. 20-21. The exhibit will be open to the public Saturday and Sunday, noon to 6 p.m. For further information contact show chairman Shawn Quealy at 466-2979.

- The Beehive State Chrysanthemum Society will have its show Saturday, Oct. 13, 3-5 p.m., and Sunday, Oct. 14, noon to 6 p.m., at the Garden Center Building in Sugarhouse Park.