Learn the mature size of the tree before you get started planting. It's one of the most common mistakes gardeners make, and the result is a tree that runs into power lines or that grows too big for its space and needs to be pruned every year. Too much pruning leads to stubs and stubs lead to rot and the rot leads to the death of some vertical limbs. Make sure you know the conditions your tree needs to grow so it can thrive. For example, a tree that needs a lot of moisture will not do well in a dry climate. Determine what you want the tree to do for your landscape. Different trees offer different things from the wow factor of cool bark to the shade from a standard maple. Choose between deciduous and evergreen. This is especially important if you are planting for privacy. You don't want to be surprised when your tree selection turns barren each winter. Different is good! Don't plant the same tree that everybody else in the neighborhood has. Not only is planting the same tree boring but it can also lead to trouble. For example, Dutch Elm Disease has wiped out trees in neighborhood after neighborhood over the last 50 years. When one tree gets sick they all get sick.
Trees will generally be the most expensive plants on your landscape shopping list. To get your money's worth, buy a good, healthy tree. Check out the leaves. You want a tree with healthy foliage. A few insect-damaged leaves is not a problem, and if you find a tree with some yellowing leaves, that's not a problem either as long as it's limited to about 10-percent of the foliage. Check the leaves for chlorosis, lack of vigor or a lack of new growth. Next, check the trunk of the tree. It should be straight. The bark should be unblemished. Cracks or soft spots can indicate frost or fungal damage. Check the rootball. If it's a balled and burlapped tree, dig down below the soil line to determine the depth it grew in the nursery and check for any girdling rope or wire that can "strangle" a tree. If it's in a container, shake the container gently to see if it's well-rooted.
You can dig a hole yourself or use an auger. An auger is a machine that has a big motor and a big drill that goes into the ground. If you have a lot of trees or a big hole to dig, an auger, even though it cost $200 or so to rent for a day, is a real time saver. First, cut the container before putting the tree in the hole. Then, don't be afraid to roll the tree on its side to make planting easier. Then, gently lower the tree into the hole and watch to make sure it's centered and not crooked. If you can, get a couple people to help if you're planting a bigger tree. It's important to remember to grab the trunk not the limbs. Don't rush the process. Get the tree right before adding any more soil. After the tree is in the ground, make sure to build a berm around the tree. The raised area of soil directs rainwater down to the root system of the tree where it really needs it for the first year or so. A berm is a narrow ledge typically at the top or bottom of a slope — a mound of earth or sand. Finally, add mulch. Mulch conserves moisture in the soil. A new tree needs a lot of moisture in order to establish itself. A berm also keeps lawnmowers from rolling into the trunk of the tree and damaging that plant you just put in the ground.
There are several tools to help water a tree. A tree ring drips water right around the trunk of the tree, right down to the root ball. It's really easy to use with a water hose. If you don't have a water hose nearby, you might want to use something different this is called a tree gator. A tree gator is just a big bag that is filled full of water and drips down to the root system of the tree. It holds about 14 gallons of water. You fill it up every couple of days and it waters the tree very nicely.