One tree is gone and now it's time to plant another in its place. It may be tempting to quickly patch up the eyesore on your property left by the removed stump and plant a new tree. The best time to plant a tree is in spring or fall, when the temperatures are moderate enough to allow the roots to grow and establish themselves. However, after stump removal, the next tree should be planted in fall; that will allow you to prepare and sterilize the area---an important step, especially if the removed tree died from disease or unknown causes.
Excavate the area as soon as possible. If you used chemicals to remove the old tree stump, dig up and dispose of any soil that came into contact with it, as the chemicals can damage your new tree.
Till the soil. Use your shovel to loosen and turn the soil and remove any large roots or rocks as you go. The area that you till should be as wide and at least half as deep as the root system of your new tree.
Sterilize the soil. One easy way to do that without using harmful chemicals is in summer, during the hottest months. Water the tilled area well enough to moisten the top 2 feet of soil. Then spread a plastic sheet over the entire area and secure it with bricks. Leave the plastic sheet to heat and sterilize the underlying soil for two months. Check the soil once every two weeks to make sure that it remains moist.
Remove the plastic after the soil has been sterilized. Spread 4 inches of compost over the soil and turn it in to the same depth that you originally dug the soil. Cover the soil with straw or some other inert mulch to prevent erosion.
Plant the new tree early in the fall. Dig a hole that is twice as wide and just as deep as the container that your tree sapling arrives in. Carefully remove the sapling from its current container and place it in the hole. Fill in the excavated soil so that it just covers the root ball of the tree.
Water the tree well by trickling water from a hose at the base of the tree until the soil is moist at least as deep as the root ball. Continue to keep the soil moist in that fashion until the tree sprouts new growth.