Tree Transplant Guide: When, How & What Size Trees Can Be Moved

Did you know that up to 50% of transplanted trees don't survive beyond one or two years? That's a hard number to hear—but it doesn't have to be your story.

Tree transplant is a bit like surgery. One wrong move, and the patient might not pull through. But when you follow the right steps, moving a tree can work beautifully.

This guide covers everything you need to know about tree transplant. We'll walk through the largest size you can move, the best season to dig, and how to avoid transplant shock. Here in Nampa, our climate gives us a solid window for successful moves—if you time it right.

By the end, you'll know exactly how to give your tree the best chance to thrive in Idaho's high desert conditions.

What is the largest size tree you can transplant?

The largest tree you can transplant depends on your equipment and the species. With professional tree spades (36" to 90"), you can move trees up to 9 to 12 inches in caliper. Evergreens can reach 30 to 35 feet tall and still be moved safely.

For DIY projects, trees under 2 to 3 inches in caliper are more realistic. Keep in mind: large-caliper trees face greater stress. One study showed 58% mortality for large red oaks compared to 0% for smaller trees of the same species.

Smaller trees often catch up in size within five years. They establish faster and bounce back quicker from the move.

Looking for trees already grown to transplant-ready size? Browse our tree farm inventory.

What Is the Largest Tree Size You Can Transplant?

Tree size is measured by "caliper." This is the trunk diameter measured 6 inches above the ground for trees under 4 inches, or 12 inches above the ground for larger trees. Caliper tells you how big a root ball you'll need and what equipment can handle the job.

Professional tree spades can move trees up to 9 to 12 inches in caliper. These machines dig a clean root ball and lift the tree in one motion. For homeowners working by hand, trees under 2 to 3 inches in caliper are much easier to manage.

Root ball sizing rule: Plan for 10 to 12 inches of root ball diameter for every inch of trunk caliper. A 4-inch caliper tree needs a root ball 40 to 48 inches wide. Go smaller, and you risk cutting too many roots.

Recovery time also scales with size. Expect roughly one year of recovery for every inch of trunk diameter. A 6-inch caliper tree may need six years to fully bounce back.

In our experience, trees over 6-inch caliper need extra watering attention for 2+ years. The larger the tree, the more you'll need to baby it through those first few seasons in Nampa's dry summers.

Best Time of Year to Transplant Trees

The best time to transplant is when the tree is dormant. In Nampa, that means early spring or fall.

Fall timing: Aim to transplant before the first hard frost. This gives roots a few weeks to settle in while the soil is still warm. In the Treasure Valley, that window usually runs from late September through mid-October.

Spring timing: Move trees before leaf-out begins. Once buds start to swell, the tree is putting energy into new growth—not root recovery. In our area, early March through mid-April tends to work well.

Nampa's high desert climate makes fall a strong choice for most deciduous trees. Cooler air temps reduce stress on leaves while soil stays warm enough for root growth. Just watch the forecast and avoid transplanting right before a cold snap.

Avoid these times:

• Summer heat puts too much stress on a freshly moved tree

• Frozen winter ground makes digging impossible and damages roots

Some species are picky. Oak, maple, birch, and beech transplant best in spring only. Their root systems need the full growing season to recover before winter arrives.

Why People Transplant Trees Instead of Cutting Them Down

Sometimes a tree is in the wrong spot but still worth saving. Transplanting lets you keep what you've grown instead of starting over.

Preservation during construction: New buildings, driveways, or fences often threaten existing trees. Moving a mature tree out of the way can save years of growth.

Environmental benefits: Mature trees store carbon, provide shade, and create habitat. A 20-year-old tree does far more work than a sapling fresh from the nursery.

Sentimental value: Maybe your grandparents planted that apple tree. Maybe you've watched it grow for a decade. Some trees carry memories worth protecting.

Cost comparison: Buying a mature tree from a tree farm can cost hundreds or thousands of dollars. Transplanting an existing tree—especially if you do the work yourself—may save money. But factor in the risk. A failed transplant means losing both the tree and your investment of time.

If transplanting feels too risky, consider nursery-grown trees ready to plant. At Melad Tree Farm, many of our trees are 5 to 10 years old. They've already done the hard work of establishing strong root systems in Idaho soil.

Step-by-Step Tree Transplant Process

Moving a tree takes planning. Rush the process, and you risk killing what you're trying to save. Here's how to do it right.

1. Root prune ahead of time (for large trees)

If your tree is over 3 inches in caliper, root prune 3 to 12 months before the move. Use a sharp spade to cut a circle around the tree at the future root ball edge. This encourages new feeder roots to grow closer to the trunk.

2. Measure and dig the root ball

Follow the 10-to-12-inch rule. For every inch of trunk caliper, dig 10 to 12 inches of root ball diameter. Dig deep enough to capture the main root mass—usually 12 to 24 inches for most trees.

3. Lift and transport safely

Never lift a tree by its trunk. The weight of the root ball can tear roots right off. Use straps under the root ball or a tree spade. Keep the root ball wrapped in burlap to hold soil in place during the move.

4. Plant at the correct depth

This is where many transplants fail. The root flare—where trunk meets roots—should sit at or slightly above soil level. Planting too deep smothers roots and invites rot.

5. Water and mulch immediately

We always water deeply within the first hour of planting. Delays hurt survival. Soak the entire root ball, then add 2 to 4 inches of mulch around the base. Keep mulch a few inches away from the trunk.

Common Tree Transplant Mistakes to Avoid

Even careful planners make errors. Here are the most common mistakes that kill transplanted trees.

Transplanting at the wrong time

Moving a tree during active growth or summer heat puts it under extreme stress. The tree is already working hard to push out leaves. Adding root damage on top of that is often too much.

Digging too small a root ball

Cutting corners on root ball size means cutting roots the tree needs to survive. Stick to the 10-to-12-inch rule. A smaller root ball might be easier to move, but it won't support recovery.

Planting too deep

This mistake is common and deadly. When the root flare sits below soil level, bark stays wet and roots suffocate. The tree may look fine for a year or two, then decline.

Skipping root pruning for large trees

Big trees need time to grow new feeder roots before a move. Without root pruning 3 to 12 months ahead, you're asking the tree to survive on whatever roots fit in the ball.

Watering errors

Both overwatering and underwatering cause problems. Nampa's dry summers demand consistent deep watering. But soggy soil rots roots. Check soil moisture before each watering.

Leaving wire baskets or burlap in place

Some pros leave wire baskets on balled-and-burlapped trees. Over time, these can girdle roots and strangle the tree. Remove or cut away as much as possible at planting.

Understanding Transplant Shock and Recovery Time

Transplant shock happens when a tree loses a large portion of its root system during a move. It's normal. But knowing what to expect helps you respond the right way.

Symptoms to watch for:

• Wilting leaves even with moist soil

• Leaf scorch or browning at the edges

• Yellowing foliage

• Little to no new growth the first season

Most trees recover within 1 to 2 years. Some take up to 5 years to fully bounce back. A good rule of thumb: expect roughly 1 year of recovery for every inch of trunk diameter.

How to help your tree recover:

Water consistently. In Nampa's hot, dry summers, this means deep soaking once or twice a week—not light daily sprinkles. Roots need moisture down where they live, not just at the surface.

Apply 2 to 4 inches of mulch to keep soil cool and retain moisture. Skip the fertilizer for the first year. Pushing new growth before roots recover does more harm than good.

When to call an arborist:

If your tree shows no improvement after two full growing seasons, get a professional opinion. Some trees need extra help. Others may not be worth saving.

We've seen trees look nearly dead the first summer, then bounce back fully by year two. Patience matters. Give your tree time before you give up on it.

Transplanting a tree is never a simple task, but with careful planning, the right timing, and consistent aftercare, it can be a rewarding way to preserve the beauty and value of your landscape. Whether you’re moving a small sapling or a mature shade tree, success comes down to preparation and patience.

By following proven steps and avoiding common mistakes, you give your tree the best chance to thrive in Idaho’s high desert climate for years to come. And when the job feels too big, remember that professional help is always available to safeguard your investment and keep your trees growing strong.

Want to learn more? Contact Melad Tree Farm today to discover our tree transplanting services and more.