Pinxterbloom azalea

Rhododendron periclymenoides

Ericaceae · [VERIFY] · native

Last updated

Data Coverage 3 of 6 dimensions
Site Data
Threats
Cultivars
Phenology
GDD Thresholds
Puget Sound

Pinxterbloom azalea (Rhododendron periclymenoides) is a deciduous shrub in the Ericaceae family reaching 3-6 ft tall with a 4-7 ft spread. It produces showy pink to white flowers and attracts hummingbirds and butterflies.

Detailed site preferences and cultivation data require further enrichment from authoritative sources. All parts are poisonous to humans, cats, dogs, and horses. The plant shares the general Ericaceae preference for acidic, well-drained soil in partial shade.

Quick Facts

Height
3–6 ft
Spread
4–7 ft
Growth Rate
Slow
Light
[Verify]
Soil
[Verify]
Water
[verify]
Hardiness
Zone Zone [VERIFY]
Bloom Time
april to may
Origin
eastern North America

Phenological Calendar

As of April 19, 2026, Puget Sound stations range from 1342.9 to 1500.8 GDD₃₂. Pinxterbloom azalea typically reaches full bloom at 1620 GDD₃₂, predicted around Apr 27.

Regional Season Tracker

GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 19, 2026
Station GDD₃₂ Current Stage Next To Go
Issaquah / East King 1,501 Pre-season Full bloom 119
Seattle / UW 1,465 Pre-season Full bloom 155
Kent / Auburn 1,441 Pre-season Full bloom 179
Olympia / Tumwater 1,415 Pre-season Full bloom 205
Bellingham / Whatcom 1,390 Pre-season Full bloom 230
Tacoma / Puyallup 1,381 Pre-season Full bloom 240
Sequim / Rain Shadow 1,343 Pre-season Full bloom 277
Stage GDD32 Typical Window
○ Full bloom BBCH 65 NEXT 1620 — est. Apr 27 (forecast)
Regional estimate
Range: 849–1031 GDD₃₂ (6yr)

GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? Source GDD₅₀ thresholds from Herms 2004 (OSU, Secrest Arboretum, Ohio) and UMD IPMnet (Gill & Klick, mid-Atlantic), converted to GDD₃₂ via Kent bloom-date mapping. Season tracker for Kent / Auburn as of Apr 19, 2026. Predicted dates use 16-day weather forecast through May 5, 2026, then climate normals.