Choose a location for your barberry plant. Pick a location that has full sun and make sure the soil does not hold water. Although the barberry likes many types of soils, it does not do well in soil that remains wet with standing water.
Dig a hole for planting. The hole should be twice as large as the root ball and the same level deep that the barberry was in its container. Separate the roots before placing in the ground. Add additional soil if needed and water well.
Add fertilizer. It is always best to fertilize young plants for strong root development. Follow the recommended instructions on the fertilizer's label for your barberry, and apply when you first put the barberry into the ground.
Prune your barberry to encourage new growth. Remove dead wood and broken limbs before trimming new wood. You should cut back shoots and take out some of the old growth after the barberry has bloomed for the summer.
Inspect your plant regularly for rust and fungi. Brown or black spots on leaves are a sign of fungi, while bright orange spots on the underside of leaves are usually a sign of rust. Remove the infected leaves and make sure to rake away any leaves that have fallen to the ground underneath the plant. If fungi is suspected, apply fungicide as directed on the label.