Planting hole size and configuration

By: YC

Planting and establishing trees is all about managing air and moisture in the soil. Manage these correctly and trees will grow quickly following planting. Three of the most common causes of poor plant establishment are
1) planting too deep,
2) under watering, and
3) over watering. Planting in compacted soil can also lead to very slow root development. Each of these problems can lead to massive tree death, poor growth, or a slow decline after planting. If appropriate trees are planted at the right depth and they are irrigated properly, the planting has a good chance of success. As simple as this appears to be, problems often arise that lead to poor establishment or plant failure.

Before digging the hole,
1) remove all soil from above the root flare, and
2) measure the distance between the top-most root and the bottom of the root ball. Dig the hole about 10% shallower than this depth and as wide as possible (at least 1.5 times the width of the ball-dig a much wider and shallower hole in compacted soil). Do not dig the hole deeper than the root ball. The root ball should be positioned in the hole shallow enough so the finished grade of the backfill soil and landscape soil is lower than the top of the root ball. In other words, leave the top few inches of the root ball sides exposed to the air. Then apply mulch so it covers the sides of the root ball. Be sure that when you are finished planting, there is NO SOIL, and little or no mulch, over the top of the root ball. Soil (as well as thick mulch layers more than 1 or 2 inches deep) over the root ball can prevent water and air from entering the root ball. When finished planting, you should be able to see the top-most root in the root ball originated from the trunk at the soil surface, or it should be within the top inch of soil in the root ball. The trunk flare should be visible.

When planting on slopes set the tree so the top-most root in the ball on the uphill side is about even with the soil. The side of the root ball on the downhill side will be well above the surrounding soil. Bring in enough soil to cover the sides of the root ball with soil. Apply mulch to finish the planting job as shown in the diagram above.