The rhododendron is a large, flowering shrub that produces pom-pom like flowers in the springtime. The plant is an evergreen, and will not lose its leaves in winter. It is hardy in USDA growing zones 3 through 8. Transplant rhododendrons in the spring to allow the roots to take hold prior to the heat of summer. Place the shrubs in an area that provides room to grow, as some varieties can reach a height of 15 feet.
Prepare a planting location that has well-draining, yet porous soil. Use a tiller to mix compost into the soil to increase the nutrient value and add moisture retention. Build a raised planting bed in areas where the soil is composed primarily of clay.
Test the soil with a home pH test kit. Reduce soil pH number and make the soil more acidic by applying agricultural sulfur. Rhododendrons prefer an acidic soil that is below a pH of 6.
Soak the root ball in a bucket of water if it is dry. Hose off the root ball if it isn’t dry to add extra moisture prior to planting. Loosen the soil around the ball but do not remove it. Cut outer roots on plants that were purchased in a container to stimulate root growth.
Dig a hole that is twice as wide as the root ball and the same height. Add a layer of compost to the bottom of the hole for moisture retention and drainage. Fill the hole with water and wait for the ground to absorb it.
Place the root ball in the hole so the top is level with the ground. Place the root ball 1 to 2 inches above the ground if the soil is less porous.
Fill the hole with a mixture of soil and compost to increase the drainage around the plant. Gently pack the soil in place.
Water the rhododendron thoroughly after planting and for the first several weeks to stimulate root growth.