Fall's cool weather suitable for tree planting

Fall is a great time to plant a tree. The soil stays warm much longer than air temperatures. Fall's cooler and wetter conditions are gentler on tree roots acclimating to their new home. And when roots awaken with spring's warmth, they have a head start over spring-planted trees.

Be sure to start with a healthy tree with roots in proportion to the leaves and no visible signs of injury to the trunk. Choose a variety of tree suitable for the site, factoring in cold hardiness, soil type and moisture levels, light conditions, and appropriate size at maturity.

Plant it correctly and give it a little extra attention after planting. A tree's death is most often a result of improper planting or care in the first couple of months. Follow these guidelines and your tree should live a long life in your landscape.

Don't plant it too deep. When planting a container-grown tree, plant it at the same depth or a bit higher than it is in the nursery pot. Look for the root flare (the bulge at the bottom of the trunk) when planting balled and burlapped trees. It may already be buried as soil built up from cultivation between the rows of trees at the nursery. Plant the tree so the root flare is just above the soil.

Dig a wide hole. While the hole should be no deeper than the root ball, it should be much wider - at least three times the diameter of the root ball (four or five times is better). The sides of the hole should slope toward the bottom.

Observe the roots. Carefully remove the tree from its pot. If roots are circling around the root ball, gently pull them outward. Make a few vertical cuts in the sides of the root ball and one in the bottom if the roots are very pot-bound. Position the tree in the middle of the hole. Once balled and burlapped trees are in the hole, remove any wire or twine and cut the burlap to uncover at least the top third of the ball.

There is disagreement whether to mix organic matter with native soil when planting a tree. Some believe roots, favoring amended soil, will circle in the same area until the tree is girdled. Others disagree, reasoning an area with amended soil provides a transition for new roots.

Shovel loosened soil around the root ball firming it with your hands as you go. Don't stomp it down with your feet. Make a watering ring around the tree with extra soil. This will hold water over the root zone as it soaks in.

Water thoroughly and apply mulch. Watering serves two purposes. It gives roots a good drink and also settles the soil. The soil should remain slightly moist, but not soggy, until the ground freezes. Water regularly if rainfall is insufficient. A deep soaking is better than sprinkling the tree with water every day.

Spread a few inches of mulch around the base of the tree, but do not volcano mulch! Keep mulch pulled an inch or so away from the trunk.

Don't fertilize at planting time. Let trees settle in to their new homes without encouraging growth. Fall-planted trees will benefit from the application of root stimulators.

Provide additional care only as necessary. This is not the time to shape the tree. Prune broken, dead or crossing branches only. There is no need to stake trees unless they are planted in an area battered by high winds.

Trees are the most important investment made in the landscape. Get them off to a good start and enjoy their beauty for a lifetime.

• Diana Stoll is a horticulturist and the garden center manager at The Planter's Palette, 28W571 Roosevelt Road, Winfield. Call (630) 293-1040, Ext. 2, or visit planterspalette.com.