When To Plant Trees In Pa

If you’re wondering when to plant trees in PA, you’ve come to the right place. Getting the timing right is the single most important step for giving your new tree a strong start in Pennsylvania’s varied climate.

Planting at the best time reduces stress on the tree and lets it focus on growing strong roots. This guide will walk you through the ideal seasons for different trees, along with simple steps to ensure your planting success.

For most trees in Pennsylvania, the absolute best times are early spring and early fall. These seasons offer the perfect balance of warm soil and cool air.

Let’s break down why these periods work so well.

Why Fall is Often the Top Choice

Many experts consider fall the premier planting season for hardy trees and shrubs. The warm soil encourages root growth, while the cooling air signals the top growth to slow down.

This means the tree can establish its root system without the pressure of supporting new leaves or flowers. By the time next summer’s heat arrives, a fall-planted tree is better settled and more drought-resistant.

Aim to plant after leaf drop but at least 6 weeks before the ground typically freezes. This is usually from mid-September through late October.
The exact window varies across PA’s zones. In warmer Zone 7 (around Philadelphia), you can plant later. In colder Zone 5 (like Erie), aim for earlier in the fall.
Fall planting is excellent for oaks, maples, pines, and most deciduous shade trees.

The Advantages of Spring Planting

Spring is a close second and is sometimes necessary. It’s the best time for more tender trees that might not handle a winter right after planting.

You want to plant as soon as the ground is workable. This is after the frost has left the soil but before the tree breaks dormancy and puts energy into major new growth.

The ideal spring window is typically from late March to mid-May in Pennsylvania.
Spring provides a full growing season for the tree to establish before winter. This is crucial for trees like dogwoods or redbuds.
Be prepared for more attentive watering, as spring-planted trees face the stress of summer heat sooner.

When to Avoid Planting

Summer is the most stressful time to plant. High temperatures and increased water demand can shock a new tree. Winter, when the ground is frozen, is simply not practical.

Late spring or early summer planting requires a very diligent watering routine and is generally not recommended for beginners. The tree will struggle more than it needs to.

Considering Your Tree Type

Not all trees follow the exact same schedule. The type of tree you’re planting can influence your ideal timing.

Bare-Root Trees

These must be planted during dormancy. Early spring, as soon as the soil can be worked, is perfect. Fall planting is also acceptable if done very early in the season.

Container-Grown or Balled-and-Burlapped (B&B) Trees

These have more flexible timing because their roots are already in soil. You can plant them in spring or fall with great success. Just avoid the peak summer heat.

Evergreens

Evergreens like spruce, fir, and arborvitae prefer early fall planting. This allows them to establish roots before winter. Late summer (early September) is also a good option, as they benefit from warm soil.

You can also plant them in early spring, but avoid late spring planting which exposes them to summer stress before they’re fully settled.

A Step-by-Step Guide to Planting Your Tree

Once you’ve chosen the right time, doing the job correctly is key. Follow these steps for a healthy tree.

Choose the Right Tree for Your Site: Match the tree’s needs for sun, soil, and space to what your yard can provide. Consider mature size—don’t plant a large oak under power lines.
Call Before You Dig: Always call 811 at least a few days before planting. This free service marks underground utility lines so you can dig safely.
Dig a Wide, Shallow Hole: The hole should be two to three times wider than the root ball. The depth should be just deep enough so the tree sits with its root flare slightly above ground level. A common mistake is digging to deep.
Handle the Roots with Care: For container trees, gently loosen circling roots. For B&B trees, remove any wire basket and cut away the burlap after placing it in the hole. Never lift the tree by its trunk.
Position and Backfill: Place the tree in the hole. Backfill with the original soil you dug out, breaking up large clumps. Avoid amending the soil with compost just in the planting hole, as this can discourage roots from expanding outward.
Water Deeply and Mulch: After backfilling halfway, water to settle the soil. Then finish backfilling and water again. Apply 2-3 inches of mulch in a wide ring around the tree, but don’t pile it against the trunk (this is called a “mulch volcano” and is harmful).
Provide Ongoing Care: Water your new tree regularly for the first two years, especially during dry periods. A slow, deep watering once a week is better than frequent light sprinklings.

Regional Considerations Across Pennsylvania

Pennsylvania’s climate varies significantly. Your local conditions will fine-tune the best planting dates.

Southeastern PA (Zones 6b-7a)

This region has a longer growing season and milder winters. Fall planting can often extend into early November. Spring can start a bit earlier, in mid-March.

Central PA (Zones 6a-6b)

This is a transition area. Stick to the core windows: April for spring, and September to mid-October for fall. Be mindful of earlier frosts in mountain valleys.

Western & Northern PA (Zones 5a-6a)

Colder winters and later springs define this area. Aim for May for spring planting and September for fall planting. Protecting young trees from harsh winter winds is more important here.

Common Planting Mistakes to Avoid

Planting Too Deep: This is the #1 cause of tree failure. The root flare (where the trunk widens at the base) must be visible above the soil line.
Over-Mulching: Piling mulch against the trunk leads to rot, disease, and rodent damage. Keep mulch away from the trunk.
Staking Unnecessarily: Most new trees don’t need staking. It can prevent the trunk from developing natural strength. Only stake if the tree is in a very windy location or is top-heavy, and remove stakes after one year.
Forgetting to Water: New trees need consistent moisture. Don’t rely solely on rain, especially in the first two growing seasons.

FAQ: Planting Trees in Pennsylvania

What is the best month to plant trees in Pennsylvania?

For fall planting, aim for October. For spring planting, April is generally ideal. These months offer the best conditions in most of the state.

Can I plant trees in Pennsylvania in the summer?

It’s not recommended. The heat and dry conditions put tremendous stress on a new tree, requiring excessive watering and increasing the risk of loss. If you must, choose a cool, cloudy period and be prepared to water almost daily.

Is it better to plant trees in spring or fall in PA?

Fall has a slight edge for most hardy trees because of the extended root-growing period. However, spring is excellent, especially for more sensitive species. Both are far superior to summer or winter.

When should you plant fruit trees in Pennsylvania?

Fruit trees, like apples and peaches, are best planted in early spring. This gives them a full season to establish before their first winter. Bare-root fruit trees must be planted in spring while dormant.

How late in fall can you plant trees?

A good rule is to finish at least six weeks before the ground freezes hard. This allows some root establishment. In practice, late October is a safe cutoff for much of PA, while early October is better for colder areas.

Choosing the right time to plant is a gift to your tree and to yourself. It sets the stage for decades of growth and beauty with less work and worry. By following these guidelines tailored to Pennsylvania’s climate, you’ll give your new tree the strongest possible foundation.