Tree Care After Planting: First-Year Establishment Guide

Tree care after planting comes down to three jobs: deep watering, a thin ring of mulch and patience. Water at least once a week when it doesn't rain, and more in hot, windy weather. Keep mulch 2 to 3 inches deep and off the trunk. Then skip fertilizer and heavy pruning in the first year.

That advice comes straight from the International Society of Arboriculture's New Tree Planting guide. Planting is only the start. What you do over the next two seasons decides whether the tree takes hold.

Why does a new tree need so much care?

A new tree needs extra care because it lost much of its root system when it was dug. The roots that came with it fit inside the root ball. Until new roots grow out into your soil, the tree can't find enough water on its own.

That gap is called transplant shock. In other words, the tree has a full set of leaves but only a fraction of its roots. So water stress in the first summer is the most common reason new trees fail.

How often should you water a newly planted tree?

Water a newly planted tree at least once a week when there's no rain. During hot, windy spells, water more often. Keep going until mid-fall, then taper off as the weather cools.

Water deep, not often

Slow, deep watering builds a strong root system. Light daily sprinkles, by contrast, only wet the top inch or two of soil. As a result, roots stay shallow and dry out fast.

For example, lay a soaker hose around the root ball, or let a garden hose trickle at the base. Cornell's horticulture team says to let water soak deep into the soil with no runoff. They also suggest digging 12 to 18 inches down nearby to check that water is getting through.

Check the soil before you water

Push a trowel into the soil beside the root ball. If it still feels moist a few inches down, wait a day. If it feels dry, water right away.

Fall-planted trees need water too. Even when the leaves are gone, the roots keep working in cool soil. Cornell advises watering trees and shrubs through October so they go into winter in good shape.

The second growing season

By the second summer, the roots have usually spread past the root ball. Still, keep an eye on long dry spells. When two weeks pass without real rain, give the tree a deep soak.

How much mulch goes around a new tree?

Spread 2 to 3 inches of mulch in a wide ring around the tree. Leave a gap of 1 to 2 inches at the trunk, as the International Society of Arboriculture advises. That gap keeps the bark dry and helps prevent decay.

Mulch holds moisture, so you water less. It also evens out soil temperature and feeds the soil as it breaks down. Check the ring each spring and fall, and top it up as it thins.

Avoid volcano mulching, the tall cone piled against the trunk. Instead, widen the ring as the tree grows, because the roots spread wider every year.

Keep grass and mowers away from the trunk

Grass right up to the trunk competes with the tree for water. A mulched, grass-free circle removes that competition. In addition, it keeps mowers and string trimmers off the bark.

Those machines cause more trunk damage than most people realize. One nick from a string trimmer can girdle a thin young trunk over time.

When should you remove tree stakes?

Remove tree stakes after the first year of growth. Many trees don't need staking at all. In fact, the International Society of Arboriculture notes that unstaked trees tend to grow stronger trunks and roots.

If your tree was staked, check the ties a few times that first year. Loosen any tie that starts to bite into the bark. After a year, if the tree still feels loose, look for a root problem rather than adding a new stake.

Should you prune a newly planted tree?

Prune a newly planted tree as little as possible. Remove only broken or dead branches. The tree needs every leaf to feed new root growth.

Shaping can wait until the tree has had a full season of growth. By then, it handles cuts much better. For young-tree structure later on, see our guide to pruning young trees.

Should you fertilize a new tree?

No, skip fertilizer at planting time. Feeding can push leafy growth that a small root system can't support. If leaves turn pale later, find the cause first. Pale leaves can come from too much water or soil pH, not just a lack of nutrients.

Signs your new tree is struggling

Watch the leaves through the first two summers. They tell you most of what the roots are doing.

• Wilting in warm weather: Check the soil first. If it's dry, water deeply and keep a steady schedule.
• Brown, crispy leaf edges: This leaf scorch usually means water stress during heat. So water more often.
• Yellowing leaves: Overwatering, poor drainage or soil pH can all cause it. Find the cause before you feed the tree.
• No leaves by late spring: A fall-planted tree may not have survived winter. Scratch a twig with your thumbnail; green underneath means it's alive.

Shawn and his crew plant trees across Dutchess County, from Poughkeepsie to Millbrook. If a new tree looks stressed, they can take a look and tell you why.

Request an assessment or see our tree planting service to get the next tree started right.