Accolade Elm
A Graceful, Glossy Hybrid Elm With Elite Disease Resistance
Accolade Elm (Ulmus 'Accolade') is a hybrid Asian elm bred by the Morton Arboretum that pairs the classic upright vase shape of a great elm with exceptional, time-proven disease resistance. Glossy dark-green leaves, fast growth, and resistance to both Dutch elm disease and elm yellows have made it one of the most widely planted American-elm alternatives — lining boulevards from Chicago to the Twin Cities since the 1980s. Hardy through USDA zone 3, it's a dependable, low-risk shade tree. Whether you want quick shade over an Eden Prairie backyard, a graceful street tree in St. Paul, or a fast ash replacement in Maple Grove, Accolade is a proven performer.
Accolade Elm Plant Details
| Attribute | Detail |
| Scientific Name | Ulmus 'Accolade' (U. davidiana × U. wilsoniana) |
| Common Names | Accolade Elm, Hybrid Elm, Morton Accolade Elm |
| Mature Height | 50–60 feet |
| Mature Width | About 40 feet — upright vase form |
| Growth Rate | Fast — about 3–5 feet per year when young |
| Sun | Full sun (6+ hrs); tolerates light shade |
| Water | Moderate. Tolerates a wide range of soils; prefers consistent moisture while establishing. |
| USDA Zones | 3–7 (Twin Cities is zone 4b–5a) — exceptionally cold-hardy |
| Soil | Highly adaptable. Tolerates Minnesota clay-loam and urban soils; prefers deep, well-drained loam. |
| Foliage | Deciduous — glossy dark-green leaves; graceful, arching vase canopy |
| Fall Color | Yellow |
| Dutch Elm Disease Resistance | Very high — a proven resistant cultivar used since the 1980s; also resists elm yellows |
| Winter Hardiness | Reliable to USDA zone 3 — proven in Twin Cities winters |
| Deer Resistance | Moderately deer-resistant; protect the trunk from buck rub the first 2 winters |
| Native Status | Not native — a Morton Arboretum hybrid of Asian elm species, bred for disease resistance and form |
Accolade Elm Uses in Minnesota Landscapes
Graceful Vase-Shaped Shade Tree
Accolade grows fast into an upright, arching vase that echoes the classic American elm silhouette, with glossy foliage that stays clean and handsome through summer. It makes a refined, fast-establishing shade tree for Twin Cities yards.
Proven Street and Boulevard Tree
Decades of use across Chicago and the Twin Cities have proven Accolade on tough urban sites. Its strong resistance to both Dutch elm disease and elm yellows makes it one of the lowest-risk boulevard elms you can plant. Keep it back from the heaviest direct road-salt spray.
Fast Replacement Tree
Quick growth makes Accolade an excellent rapid-canopy replacement for ash trees lost to emerald ash borer, restoring shade far faster than a slower-growing oak.
Best Time to Plant Accolade Elm in Minnesota
Plant in spring (late April–May, after the ground thaws) for a full growing season of root establishment, or in early fall (late August–early October) while the soil is still warm. Get it in the ground at least six weeks before the ground freezes — typically mid-November in the Twin Cities. Avoid mid-summer planting in heat and humidity, and never plant after mid-October or before spring thaw.
How to Plant Accolade Elm
- Dig wide, not deep — 2–3x the root ball width but only as deep as the ball is tall, so the root flare sits at or slightly above grade.
- Check for clay hardpan — if water pools and won't drain, break through the clay layer or mound-plant slightly to improve drainage.
- Backfill with the native soil mixed with 20–30% compost; don't build a pure-compost "container" the roots won't grow beyond.
- Spacing — give a single specimen 30–40 feet of clearance; space a boulevard row 40–45 feet apart for an arching canopy.
- Build a 3–4 inch watering ring to direct water to the roots, then flatten it before winter so it doesn't trap ice.
- Mulch with 2–3 inches of shredded bark or wood chips in a wide ring, kept 2 inches off the trunk. Never use gravel mulch in Minnesota — it doesn't insulate roots.
Watering Accolade Elm in Minnesota
First Year Watering Schedule
Weeks 1–2: water deeply and slowly every 1–2 days. Month 1–2: every 3–4 days. Month 3–6: every 5–7 days during active growth, easing off when rainfall is adequate (the Twin Cities average about 3 inches a month from June through August). Stop watering 2–3 weeks before the ground freezes — usually late October — so the tree doesn't push tender growth heading into winter.
After Year One
An established Accolade largely cares for itself, needing supplemental water mainly during extended droughts (two-plus weeks with no rain and temps above 80°F). Soak deeply to 8–12 inches every 7–14 days during dry spells and let natural rainfall do the rest.
Will Accolade Elm survive a Minnesota winter? Yes — easily. It's rated to USDA zone 3 and is reliably hardy in Twin Cities winters. Wrap the young trunk the first winter to prevent sunscald and buck rub.
Is it resistant to Dutch elm disease? Yes — very high resistance, and it also resists elm yellows. Accolade has been a primary American-elm replacement since the 1980s with an excellent track record. No elm is fully immune, but Accolade is among the most reliable.
How fast does it grow here? Fast when young — about 3–5 feet per year — which makes it one of the quickest shade trees to establish a usable canopy.
Is it native to Minnesota? No — Accolade is a hybrid of Asian elm species, bred at the Morton Arboretum. If you'd prefer a native, our American elm selections (Valley Forge, Princeton, New Harmony, Jefferson, St. Croix, Prairie Expedition) are Ulmus americana.
Does it tolerate clay and urban soil? Yes — exceptionally well. Accolade handles compacted, clay, and tough city soils, which is a big part of its long popularity as a boulevard tree.
You May Also Like
- Triumph Elm — a closely related glossy hybrid elm with a vigorous vase form.
- New Horizon Elm — a fast, upright hybrid elm with near-immune DED resistance.
- Valley Forge Elm — the most DED-resistant native American elm, with a classic arching vase.
- Princeton American Elm — a classic DED-resistant native American elm.
- Greenspire Littleleaf Linden — a tough, uniform boulevard tree with fragrant pollinator bloom.
How Many Accolade Elm Do I Need?
Accolade is a large, vase-shaped shade tree maturing around 40 feet wide, so it is almost always planted as a single specimen rather than in a hedge. Give one tree 30–40 feet of open space from buildings and other large trees. For a matching boulevard or driveway row, space trees 40–45 feet apart so the arching canopies meet overhead without crowding. For an informal grove on a large property, plant a loose group of 3 spaced 35–40 feet apart.
Accolade Elm Season-by-Season in Minnesota
- Spring: Leafs out early with glossy dark-green foliage; small reddish flowers open before the leaves but are barely noticeable.
- Summer: The dense, arching vase canopy throws cool, even shade, and the clean foliage resists the leaf scorch and disease that plague older elms.
- Fall: Foliage turns a clear yellow before dropping.
- Winter: Bare branches reveal the classic upright vase silhouette against the snow.
At a Glance
✔ Pollinator-Friendly ✔ Deer-Resistant ✔ Drought-Tolerant (once established)
Plant It With
- Greenspire Littleleaf Linden — another tough boulevard shade tree with fragrant pollinator bloom.
- Princeton American Elm — pair the hybrid with a classic native elm for a matched street planting.
- Redmond Linden — fast native shade with fragrant midsummer flowers.
- Black Hills Spruce — a dense evergreen backdrop that frames the elm's open canopy year-round.
Is Accolade Elm Right for Your Yard?
Accolade thrives in full sun and open space with room for a 40-foot canopy, and it shrugs off the clay, compacted, and urban soils that defeat fussier trees. It carries the strongest class of Dutch elm disease resistance and handles moderate deer pressure. Not a fit if you have a small lot, plant it directly in the heaviest road-salt spray zone, or want a tree that stays under 30 feet — for tight spaces choose a narrow Boulevard Linden or a columnar selection instead.