Henry David Thoreau often referred to trees as old friends, a feeling shared by many gardeners. Trees offer shade, beauty and a place to hang a swing. They require little in return. Because trees take so long to grow, we become more attached to them than other plants. We are saddened when a tree must be cut down due to disease or storm damage. Choose trees carefully because you'll have them for many years. One of the biggest mistakes gardeners make is buying a tree that will eventually become too big for the space allotted. Consider the growing needs of the tree, as well as potential problems.
Consult a local extension office or nursery specialist for trees that thrive in your area. Consider the soil type, sun, space and moisture level of your garden. Trees are a major investment and removing them is cumbersome, so it's important to choose a tree suitable for your yard.
Measure the root ball's width and height with a measuring tape. Dig a hole twice as wide and as deep as the root ball of the tree. Lay the soil on a tarp for convenience.
Add four shovelfuls of compost to the dirt on the tarp and mix thoroughly with a shovel. If your soil is very compacted, add two more shovelfuls. Stand in the bottom of the hole and tamp down on the soil with your foot. This prevents the soil from settling once the tree has been planted, creating air pockets around the roots.
Remove the tree from its nursery pot or cut off the burlap with a knife. Place the tree carefully in the hole. Depending on the species, the tree should sit 1 to 2 inches above the surrounding soil. If necessary, remove the tree and add more soil.
Backfill the hole with soil until half-full. Fill the hole with water from a slow-trickling hose. Allow the hole to drain and then fill completely with soil, mounding it up 2 or 3 inches around the trunk of the tree. Water again for 20 minutes. Apply a 2-inch layer of wood chip mulch to the base of the tree to conserve moisture.
Place a cylinder of hardware cloth around the trunk to deter deer and rodents from nibbling on it. Cover the trunk in burlap or a commercial tree wrap to protect it from cracking and sunscald during winter. Remove the wrappings in early spring.
Water young trees weekly during dry periods. Lay a slow-trickling hose on the ground near the tree for one hour once a week if you haven't received rainfall. Most older trees don't need fertilizer, but fertilize young trees in the fall with a 10-10-10 pelleted fertilizer. Use 2 lbs. for each inch of the tree's diameter and water the tree after application.
Watch for signs of disease or pests, including broken, blackened twigs and spotted leaves. Consult a local tree specialist to positively identify the disease or pest and suggest appropriate treatments.