Planting Containerized Trees and Shrubs

horticulture staff planting a tree at Reiman Gardens

May is considered the ideal time to plant containerized trees and shrubs in Iowa.

  • Select an appropriate location for the plant. Look up how tall and wide the plant gets before you plant it. If planted too close together, or too close to a structure, they will look overgrown. Find out which conditions a plant grows best in, including light and water preference.
  • Dig the hole shallow and wide. The hole should be 1.5 to 2 times the width of the container, but no deeper than the container’s soil line.
  • ‘Box’ the roots. Shaving a little off the four sides and bottom of the root ball encourages new roots to form. If a plant stays in a container for too long the roots will start to circle at the edge of the pot. If it is planted without redirecting the roots, the roots will grow into each other as they get larger, eventually hurting or killing the plant. ‘Boxing’ the root ball removes these girdling roots, and the new roots will grow outwards.
  • Plant at the right height. Set the plant in the center of the hole, make sure the root flair is above ground for trees
  • Break up soil and gently backfill the hole. Large clumps of soil need to be broken up to ensure no large air pockets form. Settle the soil by watering and lightly patting it down. There is no need to include compost or fertilizer at planting time.
  • Remove plastic tags and prune broken branches. Tidy up the plant and make sure no string or plastic is left around branches. Broken branches should be removed so that wounds can start healing properly.
  • Mulch the planting area. Use 1-3” of mulch near new plants. This keeps soil temperature near the roots cool in the summer, holds water, and helps to prevent competition from weeds. Try to keep a small ring directly around the base of the plant free from mulch.

Happy planting!