Species

Ulmus americanaAmerican Elm

4 other cultivars

treeN. America Native

Jefferson American Elm

Ulmus americana 'Jefferson'

The Story

Plant Bio

Ulmus americana, the American elm, is a large deciduous tree native to eastern and central North America, where it grows on floodplains and moist riverbanks. The species is characterized by its broad-spreading, vase-shaped canopy and rough-textured, doubly-serrate leaves that turn yellow in the fall.

'Jefferson' is a highly disease-resistant cultivar selected for its exceptional resistance to Dutch elm disease and its structurally superior, wide-angled branch unions. The foliage emerges earlier in the spring and retains its deep green color longer into the fall than the wild species.

Uses & Benefits:

Features a classic, broad-spreading, vase-shaped canopy with dark green foliage that turns bright yellow to bronze in fall.

Highly tolerant of urban pollution, compacted soils, and temporary flooding, making it an exceptional street and shade tree.

Provides nesting sites and cover for songbirds, while its spring-ripening samaras serve as a food source for small mammals.

SpeciesUlmus americanaAmerican Elm

Essentials

At a Glance

Plant Type

Tree

Height

590"

Width

590"

Light

Full Sun, Partial Sun

Zones

4, 5, 6, 7, 8, 9

Water

Medium

Humidity

Medium

Lifespan

Long

Native To

North America

Toxicity

Non-toxic

Bloom period

Early spring – Late spring

In flower about 3 months of the year

Planting

How to Grow

Select a planting site in full sun to partial shade with moist, well-draining loam, though clay and dry soils are also tolerated.
Dig a hole twice as wide as the root ball and of equal depth, ensuring the root flare sits slightly above the surrounding soil grade.
Backfill with native soil, water deeply to settle the roots, and apply a three-inch layer of organic mulch around the base, keeping it clear of the trunk.
Water regularly during the first two growing seasons to establish a deep, drought-tolerant root system.

Pro Tip

Avoid pruning during the spring and summer when elm bark beetles are active, as fresh cuts release volatile compounds that attract these disease vectors.

Keep It Thriving

Care Guide

Do

Prune strictly during late winter dormancy to minimize the risk of attracting disease-carrying beetles.
Apply a balanced organic fertilizer in spring if planting in nutrient-depleted urban soils.
Mulch the root zone annually to conserve moisture and regulate soil temperature.

Don't

Do not prune during spring or summer when elm bark beetles are actively flying.
Do not allow young trees to dry out completely during extended drought periods before they are fully established.
Do not plant near power lines or structures where its broad, mature canopy will cause interference.

Seasonal Care Calendar

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

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Shade TreeStreet TreeUrban ParkwaysReclamation Sites

Companion Plants

Acer rubrum Liriodendron tulipifera Symphyotrichum novae-angliae

Multiply

Propagation Methods

Good to Know

Common Questions

Jefferson American Elm questions

What zones can Jefferson American Elm grow in?

Jefferson American Elm is hardy in USDA Zones 4–9. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Jefferson American Elm deer resistant?

Not reliably. Deer may browse Jefferson American Elm, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Jefferson American Elm bloom?

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

Does Jefferson American Elm need full sun?

Jefferson American Elm does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Jefferson American Elm drought tolerant?

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