Coralburst Crabapple

Full bloom

Malus 'Coralcole'

Rosaceae · broadleaf deciduous tree · introduced

Last updated

Malus 'Coralburst' (Rosaceae) is a compact deciduous crabapple cultivar, typically grafted onto a standard to form a small, rounded tree. Double coral-pink flowers appear in profusion in spring. Small persistent fruit follows.

Coralburst performs best in full sun on well-drained soil. Bloom begins around 217 GDD (base 50 F) with full bloom near 263 GDD, making it one of the earlier-blooming crabapple cultivars. Its compact size suits smaller garden spaces and street tree plantings.

Coralburst® is a useful semi-dwarf crabapple for tight Puget Sound residential spaces — under utility lines, between sidewalk and house, in courtyards and entry alcoves. The top-graft lollipop form gives a clean, formal appearance that fits well in urban hardscapes where a multi-stem natural-form crabapple would look unkempt. The 15 × 15 ft mature size is genuinely compact: this is one of the only crabapples that stays small enough for sidewalk planting strips. Disease performance is the major regional caveat: while fire blight, rust, and mildew resistance are excellent, the moderate scab susceptibility (rated MS here based on JFS Fair and conservative PA/IL regional trials) is a real concern in maritime PNW where cool wet springs produce heavy scab pressure most years. Expect some defoliation in scab-heavy years; foliage already tends to look dull by midsummer per Johnson's Nursery observations. If scab tolerance is a priority, ‘Adirondack' or 'Prairifire’ are better choices for the region. Where the compact form is required and moderate scab is acceptable, Coralburst® remains a defensible pick. The octaploid heritage produces semi-double flowers that read more like a mid-spring flowering cherry than a typical single-flowered crabapple — a distinct ornamental character worth noting when selecting for visual effect. Alternate-year bearing means flower density varies dramatically between seasons; plan companion plantings accordingly.

— Chris Welch, ISA Certified Arborist

Plant Profile

Size & Form

Height
15 ft
Spread
15 ft (mature crown spread; equal to height producing a 1:1 rounded profile)
Growth Rate
Slow (reaches 15 ft over ~20 years; semi-dwarf habit)
Size at 20 yr
15 ft (semi-dwarf habit means little additional growth thereafter)
Lifespan
50-80 years typical for ornamental crabapples

Site Requirements

Light
Full sun (best flower production and disease resistance); tolerates light afternoon shade with reduced flowering and increased scab pressure
Soil Drainage
Well drained; avoid waterlogged or low lying sites; cultivar tolerates seasonal moisture but root rot risk increases on saturated heavy clay
Soil pH
5.5-7.5 (slightly acidic to neutral); tolerates mildly alkaline conditions
Water
Moderate
Drought Tolerance
Moderate; established trees tolerate seasonal drought typical of pnw summers; supplemental watering benefits flower production and reduces dieback
Hardiness
Zones 4a–8b

Ornamental Interest

Bloom Time
late April to mid-May (Puget Sound); early- to mid-spring blooming; one of the earlier-blooming crabapples in the recommended set, useful as a complement to mid- and late-blooming cultivars like Adirondack
Fall Color
Insignificant (foliage drops without notable color; foliage often appears tired by late summer)
Origin
Cultivar from open-pollinated seedling of Malus sieboldii (parent native to China
Watch for this season

Bloom Infection Window

Active Conidial Spread

First Flight

Diseases: Regionally Documented (3)

Diseases: Other Associations (1)

Pests: Regionally Documented (3)

Phenological Calendar

As of June 3, 2026, Puget Sound stations range from 2435.5 to 2672.8 GDD₃₂. Coralburst Crabapple has passed full bloom (1184 GDD₃₂).

Regional Season Tracker

GDD₃₂ accumulation across 7 Puget Sound stations · as of Jun 3, 2026
Station GDD₃₂ Current Stage Next To Go
Issaquah / East King 2,673 Full bloom
Kent / Auburn 2,665 Full bloom
Seattle / UW 2,610 Full bloom
Olympia / Tumwater 2,570 Full bloom
Tacoma / Puyallup 2,535 Full bloom
Bellingham / Whatcom 2,533 Full bloom
Sequim / Rain Shadow 2,436 Full bloom
View full calendar (2 stages)
Stage GDD32 Typical Window
Beginning of flowering BBCH 61 977 Mid- to late April (Puget Sound); 'Coralcole' is an earlier-blooming cultivar than many crabapples
Full bloom BBCH 65 NOW 1184 Late April to early May (Puget Sound)
Range: 635–790 GDD₃₂ (6yr)

Source: OSU phenology catalog (OSU: weather.cfaes.osu.edu) About GDD₃₂ →

Season tracker for Kent / Auburn as of Jun 3, 2026. Predicted dates use 16-day weather forecast through Jun 19, 2026, then climate normals.

Data Maturity
Structured Multiple sources. Expert review underway.