Species

1 other cultivar

‘Patriot’Patriot Elm

tree

Prospector Elm

Ulmus wilsoniana 'Prospector'

The Story

Plant Bio

Elms are large, graceful deciduous trees, historically cherished for their classic vase-shaped canopy that provided ideal shade for streets and homes.

'Prospector' is a U.S. National Arboretum introduction highly valued for its excellent resistance to Dutch elm disease and good resistance to elm leaf beetle. It develops the classic, upright-arching vase shape of the American elm.

Uses & Benefits:

'Prospector' restores the classic, elegant vase shape of the beloved American elm to landscapes. Its arching branches create a beautiful silhouette, and its dense green foliage provides excellent shade before turning a pleasant yellow in the fall.

Its primary practical benefit is its high resistance to Dutch elm disease, allowing for the confident planting of a large, long-lived shade tree. It is also tolerant of urban conditions, including pollution and various soil types, making it a tough street tree.

Elms are host plants for the caterpillars of several butterfly species, including the Mourning Cloak and Eastern Comma. The seeds are eaten by birds and small mammals, and the large canopy provides nesting sites.

Essentials

At a Glance

Plant Type

Tree

Height

540 inches

Width

420 inches

Light

Full Sun

Zones

4, 5, 6, 7

Water

Medium

Humidity

Adaptable

Lifespan

60-100+ years

Native To

China (Species)

Toxicity

Non-toxic

Bloom period

Early spring

In flower about 1 month of the year

Planting

How to Grow

Choose a location in full sun with room for a large tree.
Plant in moist, well-drained soil; elms are widely adaptable.
Dig a hole two to three times the width of the root ball.
Set the tree so the top of the root ball is level with the soil.
Backfill with native soil and water deeply to settle.
Water regularly for the first two years to ensure establishment.

Pro Tip

Focus on structural pruning when the tree is young to develop a strong, well-spaced framework of branches for a durable, long-lived tree.

Keep It Thriving

Care Guide

Do

Prune in the dormant season to maintain a single central leader when young.
Provide supplemental water during extended droughts.
Mulch the root zone to conserve moisture and moderate soil temperature.

Don't

Do not prune elms from April through August to avoid attracting bark beetles.
Avoid soil compaction over the root zone from vehicles or heavy foot traffic.
Don't plant it under power lines due to its ultimate height.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Pest Check
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Excellent disease-resistant street treeGraceful shade tree for large lawns and parksStately specimen with a classic vase shape

Companion Plants

Hydrangea arborescens 'Annabelle'Hosta 'Sum and Substance'Vinca minor Tiarella cordifolia Acer saccharum

Multiply

Propagation Methods

Good to Know

Common Questions

Prospector Elm questions

What zones can Prospector Elm grow in?

Prospector Elm is hardy in USDA Zones 4–7. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Prospector Elm deer resistant?

Yes — Prospector Elm is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Prospector Elm bloom?

Prospector Elm typically blooms in early spring through early spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Prospector Elm need full sun?

Prospector Elm does best in full sun (6+ hours).

Is Prospector Elm drought tolerant?

Yes — once established (usually after the first full season), Prospector Elm handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.