Planting a tree in pure gravel is nearly impossible. Trees require additional nutrients and water that gravel cannot provide. However, it is possible to plant trees in a gravel bed that has well-drained, nutrient-rich soil underneath the gravel. Planting the tree under the gravel and replacing the gravel back around the tree will produce a planting bed that resists weeds and pests. For hardy trees, this environment is close to ideal and the trees will thrive.
Prepare the gravel for planting. Shovel away all of the gravel until you reach the soil below. Prepare a bed 10 feet by 10 feet. Place 2 inches of compost over the surface of the soil. Place another 2 inches of mulch on top of the compost mixture.
Shovel the additives into the top 24 inches of soil. Mix the soil mixture into the remaining gravel.
Dig a hole twice as big as the root ball and half as deep. Unwrap the root ball and place the tree inside. Make sure half of the tree’s roots sit above the soil line.
Replace the gravel around the base of the tree. Make sure to pile the gravel no higher than where the tree roots and truck connect.
Water the tree at least once a week for 30 minutes at a time. Continue to water this way for the first year of growth.
Trees planted in gravel will get more sunlight than trees planted in regular soil. The gravel will reflect the sunlight back onto the tree. Only plant trees that love continual sunlight in a gravel bed. Desert plants make ideal gravel-bed trees. Choose a tree that can grow in sandy or dry conditions. Gravel absorbs water quickly and does not retain water for long periods of time. Because of this, the tree that you choose should be able to grow in small amounts of water. Red cedar, pin oaks, red pine, white spruce or sour gum trees will all grow well in quickly draining soils. Choose a tree that has a root ball at least twice as large as the tree top.
Do not plant trees that require a lot of moisture in gravel beds. Trees that have a deep root system, such as pine trees, work well around gravel because they are able to find nutrients and water deep in the soil under the gravel.