Allow the soil in the palm's potting container to dry out slightly prior to transplanting the palm to outdoors. This will make the tree easier to extract from the container on transplant day.
Select a location that does not interfere with power lines or underground water and septic lines. Mature palm trees require a space with a minimum 10-foot diameter for growing room, and many will reach a height of 15 feet.
Measure the height and width of the palm's container, then dig a hole that is three times the depth and diameter of it. This will allow ample room for additional starter soil and the root ball.
Fill a 10-gallon bucket half full with organically enriched potting soil. Fill the remainder of the bucket with peat moss. Mix well to combine the two soil mediums.
Fill the bottom of the hole with 1 inch of the soil mixture from the bucket. Water until the mixture is wet. Allow the water to drain and the soil medium to settle, then add another inch of soil mixture to the hole.
Open the blades on a pair of sharp pruning shears. Spray both sides of the blade with a mild disinfectant spray. Prune 1/2 to 1/3 of the tree's leaves, cutting the oldest leaves and leaving new growth, advises the University of Florida IFAS Extension. This will enable the tree to better utilize water and soil nutrients after transplant.
Measure 6 inches out from the hole and dig a 2-inch irrigation ditch around the hole at that distance from it. Fill the ditch with water.
Extract the palm tree from the container. Pour rooting hormone powder in a large bowl. Dip the end of a small paint brush into the powder. Dust the powder onto the palm roots until all the roots are generously coated. Rooting hormone builds a stronger root system to help keep the palm from toppling as it matures, advises the University of Florida IFAS Extension.
Stand the palm tree in the hole. The bottom inch of the tree's trunk must be buried during the transplant, so align the palm tree with the soil line accordingly.
Backfill the hole with any remaining potting mixture from the bucket. Use dirt dug from the hole to finish backfilling. Water the palm tree until the ground is soaked. Allow water absorption and dirt settlement by waiting approximately 10 to 15 minutes. Backfill with additional dirt until the dirt is level with the existing soil line.
Measure 12 inches from the trunk of the newly transplanted palm tree. Apply a time-released nitrogen-based fertilizer around the diameter of the tree. Transplanted palms from containers require additional nitrogen for the first 6 months after transplant, says the University of Florida IFAS Extension.
Water the base of the palm tree until the ground is wet, but not saturated with standing water. Fill the irrigation ditch with water.