Pear trees grow well in hardiness zones 4 through 9, making most of Washington state's climate ideal for this fruit tree. The colder areas east of the Cascade mountains are generally in Zone 5 and the warmer areas on the east side of the Cascades can range from Zone 8 to Zone 9. But because pear trees tend to require between 1,000 and 1,200 hours of temperatures below 45 degrees Fahrenheit, they may do better at higher elevations in either the Cascades or the Olympic mountains for optimal fruiting.
Select a healthy dormant tree in late fall. If dormant trees aren't available, get your trees as early as possible in the spring. Planting in fall will ensure that the trees start growing as quickly as possible in the spring and will ensure a more robust tree for the following winter. If you are in eastern Washington, plant as early as possible in the spring to avoid cold damage to the roots of the young trees.
Place the trees you will be planting in water for about an hour before planting. A large bucket, pan or even a wheelbarrow will work.
Dig a hole, or holes if you are planting multiple trees, slightly larger than the root ball of your young tree. A hole 18 inches wide and deep is usually sufficient.
Remove any dead or broken roots with a pair of pruning shears. Shorten any roots that are wider than your hole with a pair of shears.
Set the tree in the hole so the trunk is at the same level with the surrounding ground as it was in the nursery pot. The highest root should be around 4 inches below the soil when the hole is backfilled.
Fill the hole half way and tamp down the soil to ensure good root to soil contact. Add several inches of water to the half-filled hole.
Finish filling the hole and give the newly planted tree around 2 gallons of water.
Remove the top of the newly planted trees by clipping it 36 inches above the ground with a pair of pruning shears. This will encourage branching over the first four years.
During the tree's first winter, about 30 days before the tree begins growing leaves, remove most of the upward growing leaders. Keep the two strongest leaders. These two leaders should be growing approximately opposite each other to maintain tree balance.
During the tree's second winter, again about 30 days before the tree begins growing leaves, remove weak or competing leaders to encourage growing and strengthening on main leaders and branches.
During the tree's third winter, prune again as you did the previous year. This is the last winter for early pruning. You should do all future prunings around 30 days before the tree grows leaves. Future prunings will be to maintain health and vitality, to remove deadwood, and to deal with any branches that cross.