The oak tree is a deciduous broadleaf tree variety that is hardy to plant in growing zones 4 through 9 depending on the variety. The tree is commonly planted in home landscapes for shade as it grows to a height of 100 feet and spread of 50 to 80 feet. Oak trees have a large root zone which extends past the tree foliage to a distance of one-third the length between the trunk and the foliage.
Location and Soil
An oak tree requires planting in a location that has a well draining soil, preferably sandy or loam, and an acidic pH. Choose an area that offers the oak tree full sun to partial shade light conditions. Use a home pH soil test kit to find the pH and add ground rock sulfur to amend the soil and make it more acidic if needed.
Oak trees do not require excess watering during most of the year. The trunk of the tree should remain dry to prevent the introduction of disease. Water the tree during periods of drought by soaking the outer two-thirds of the root zone area ground to a depth of 1 to 2 feet.
Oak trees benefit from applying a 4 inch thick layer of bark mulch over the soil surface around the tree. Leave a 6 inch gap between the start of the mulch and the tree trunk and do not apply more than a 4 inch layer. A mulch application will assist with moisture retention and prevent weed growth that may compete with the oak tree’s root growth.
Oak trees should only be pruned to remove dead or damaged branches or to correct a structural problem. Prune an oak tree during the winter dormant season and remove no more than 10 percent of live branches during one pruning session. Excessive pruning of an oak tree will open the interior branches to sun scald and may stimulate new growth that can reduce the vigor of the tree. Disinfect all pruning equipment prior to use with a solution of 9 parts water and 1 part bleach. This will prevent the spread of disease when the branches are cut.
Oak trees do not require regular fertilizer treatments throughout the growing season as the tree pulls nutrients from the soil as leaves and other debris decompose in the root zone. Apply a nitrogen fertilizer if the oak tree has poor growth or displays signs of debris. Spread the fertilizer in the outer two-thirds root zone area and water to increase absorption into the roots.