P.J.M. Rhododendron
Rhododendron pjm
Ericaceae · broadleaf evergreen shrub · introduced
Last updated
Data Coverage 4 of 6 dimensions
Quick Facts
Height
3–6 ft
Water
Moderate
Hardiness
Zone Zones 4a–8b
Phenological Calendar
As of April 3, 2026, Puget Sound stations range from 1070 to 1180.6 GDD₃₂. P.J.M. Rhododendron has passed 'full bloom' (1032 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 3, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,181 | 'Full bloom' | — | — |
| Seattle / UW | 1,171 | 'Full bloom' | — | — |
| Kent / Auburn | 1,111 | 'Full bloom' | — | — |
| Olympia / Tumwater | 1,106 | 'Full bloom' | — | — |
| Bellingham / Whatcom | 1,101 | 'Full bloom' | — | — |
| Tacoma / Puyallup | 1,075 | 'Full bloom' | — | — |
| Sequim / Rain Shadow | 1,070 | 'Full bloom' | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'First bloom' BBCH '61' | 853 | '' |
| ● 'Full bloom' BBCH '65' NOW | 1032 | '' |
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? Hover over GDD values for source details. Season tracker for Kent / Auburn as of Apr 3, 2026. Predicted dates use 16-day weather forecast through Apr 19, 2026, then climate normals.
Diseases (28)
Phytophthora spp. Root Rot (Phytophthora spp.) Podosphaera aphanis var. aphanis Powdery Mildew Ovulinia azaleae Ovulinia Petal Blight Non-pathogenic (iron deficiency) Lime-induced Chlorosis Symptom category — not a single disease Leaf Spot Exobasidium vaccinii Leaf and Flower Gall Cylindrocladium scoparium Cylindrocladium Blight and Root Rot Botrytis cinerea Botrytis Petal Blight Xylella fastidiosa or abiotic Marginal leaf necrosis Rhododendron and Cutting Rots Non-pathogenic (abiotic stress) Leaf Burn abiotic (drought, heat stress) or bacterial (Xylella fast... Leaf Scorch Phytophthora spp. Phytophthora Root Rot and Wilt Phytophthora ramorum Ramorum Leaf Blight Botryosphaeria dothidea Botryosphaeria Dieback Seifertia azaleae Bud Blight Rhododendron necrotic ringspot virus Necrotic Ringspot Many different Phytophthora Blight and Dieback Phytophthora ramorum"filthy five\" genera are inc Ramorum Leaf Blight and Shoot Dieback Thekopsora minima and Naohidemyces vaccinii Rust Taphrina wiesneri Witches' Broom Armillaria ostoyae Armillaria Root Rot Botrytis cinerea Botrytis Shoot Blight Pestalotiopsis sydowiana Gray Blight Non-pathogenic (physiological disorder) Physiological leaf spot Phytophthora spp. Phytophthora Blight Phytophthora spp. (P Phytophthora Root Rot Phytophthora ramorum Ramorum leaf and shoot blight (Sudden oak death)
Pests (21)
Tetranychidae Spider mite Otiorhynchus spp. Root weevil Choristoneura rosaceana Obliquebanded Leafroller Caloptilia azaleella Azalea leafminer Stephanitis pyrioides Azalea Lace Bug Acanthococcus azaleae Azalea bark scale Salt injury Sunburn Tissue Proliferation Aphidoidea Aphid Lepidoptera Caterpillars Parthenolecanium spp. Lecanium scale Stephanitis rhododendri Rhododendron lace bug Dialeurodes chittendeni Rhododendron whitefly Nematus lipovskyi Azalea sawfly Tingidae Lace bug Stephanitis spp. Azalea and rhododendron lace bug Cacoecimorpha pronubana Carnation tortrix Icerya purchasi Cottony cushion scale Coleotechnites huntella Rhododendron bud moth Nematode, Stunt