Planting and mulching a tree the right way

When to plant

ISA calls the dormant seasons ideal for planting trees: fall after the leaves drop, and early spring before the buds break.¹

Planting, step by step

1. Call 811 first Ohio law requires at least two working days’ notice before you dig, not counting the day you call.²
2. Find the root flare The flare is where the trunk widens into the roots. It should be partly visible once the tree is planted. If soil covers it in the pot or root ball, remove the extra soil first.¹
3. Dig wide and shallow Make the hole two to three times wider than the root ball and no deeper than it. Most of a tree’s roots grow in the top 12 inches of soil.¹
4. Remove wrapping and wire Take any cover off the root ball and trunk. Remove a wire basket, or cut off the top one or two rings so it sits low. Straighten, cut or remove circling roots.¹
5. Backfill firmly Fill the hole firmly to get rid of air pockets, watering as you go. Skip fertilizer at planting time.¹
6. Stake only if needed Trees that are not staked develop stronger trunks and roots. Bare-root trees and windy sites may need stakes; take them off after the first year of growth.¹
7. Mulch flat, not piled Spread 2 to 3 inches of mulch as wide as is practical, and keep a mulch-free ring of 1 to 2 inches at the base of the trunk.¹³
8. Water on a schedule Water at planting, then on the schedule below until the roots are established.⁴¹

Why volcano mulching hurts trees

A “mulch volcano” is mulch heaped up against the trunk. Ohio State University Extension’s Joe Boggs explains that piled mulch compacts as it breaks down and starts to behave like soil. Roots grow up into the mound, and some wrap around the trunk and become stem-girdling roots. Signs include flat sides on the trunk just above the mulch line, splitting bark and thinning canopies.³

The damage builds slowly, which is part of why the habit hangs on, and root changes caused by mulch volcanoes can last for the life of the tree. Mulch “moats”, trenches dug around the ring, cut off roots that grow past the edge.³

How much and how often to water

• Weeks 1 to 2: water daily.⁴
• Weeks 3 to 12: water every two to three days.⁴
• After 12 weeks: water weekly until roots are established. Skip a watering only after a heavy rain, more than about an inch in a day.⁴
• Trees: about 1 to 1.5 gallons per inch of trunk diameter each time, measured 6 inches above the root flare.⁴
• Shrubs: about a quarter to a third of the volume of the pot it came in.⁴

ISA suggests watering at least once a week when it does not rain, more in hot or windy weather, and continuing until mid-fall.¹

Establishment takes a while. University of Minnesota Extension estimates about a year and a half for a tree with a 1-inch trunk and three years for a 2-inch trunk.⁴