Few trees are as graceful as the white birch, Betula pendula, an upright tree with white bark, lacy, pendulous side branches and small leaves. Native to Europe and Asia Minor, it is hardy in all areas of Washington state in the U.S. and thrives both east and west of the mountains if given plenty of water. It eventually reaches 30 to 40 feet in height and half that in width, and is especially suitable for planting in small groves.
Choose a place for your birch that is easy to water or has plenty of water naturally. Stream edges are excellent places for birches to grow though they dislike soggy, poorly drained soil. Even in rainy western Washington you need to plan for providing constant moisture during the summer. East of the mountains, your tree will do best with extra water during the dry spells in winter as well as during summer heat.
Dig a hole that is at least a foot wider and deeper than the root ball of your birch tree. If it is in a container, take it out and gently spread the roots out as much as possible to estimate the diameter of the hole needed.
Mix the soil taken from the hole with organic matter such as compost, peat moss, manure or coconut coir. All these materials help to hold water and nourish the young tree.
Fill the bottom of the hole with the improved soil deep enough to support the birch so that the top of the root ball is level with the top of the soil. Spread the roots and work the rest of the improved soil through and around them, gradually filling the hole to the top.
Water thoroughly to a depth of at least a foot and then water regularly throughout the first summer, never letting the soil dry out. During the second year, you can allow the top inch or two of ground to dry, but your birch tree will be quite happy with as much water as it can get.