Monterey Ceanothus
Ceanothus cuneatus var. rigidus
Rhamnaceae · broadleaf deciduous shrub · native
Last updated
You encounter Monterey Ceanothus as a densely branched shrub variant with rigid growth habit, representing a specialized form suited to coastal and rocky sites. The cultivar Snowball offers white flowers and compact growth (3-6 feet), distinguishing it from the parent species.
This ceanothus performs best in full sun with low water needs and excellent drainage; avoid wet, heavy soils. It tolerates poor, infertile sites well. Monterey Ceanothus expects the same pest and disease pressures as the species: leaf spot and root rot in heavy, wet conditions. Prune in late winter or early spring. Limited specific data exists for this variety; consult parent species guidance when management questions arise.
Quick Facts
Phenological Calendar
As of April 3, 2026, Puget Sound stations range from 1070 to 1180.6 GDD₃₂. Monterey Ceanothus typically reaches 'first bloom' at 1334 GDD₃₂, predicted around Apr 14.
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 | Pre-season | 'First bloom' | 153 |
| Seattle / UW | 1,171 | Pre-season | 'First bloom' | 163 |
| Kent / Auburn | 1,111 | Pre-season | 'First bloom' | 223 |
| Olympia / Tumwater | 1,106 | Pre-season | 'First bloom' | 228 |
| Bellingham / Whatcom | 1,101 | Pre-season | 'First bloom' | 233 |
| Tacoma / Puyallup | 1,075 | Pre-season | 'First bloom' | 259 |
| Sequim / Rain Shadow | 1,070 | Pre-season | 'First bloom' | 264 |
| Stage | GDD32 | Typical Window |
|---|---|---|
| ○ 'First bloom' BBCH '61' NEXT | 1334 | '' est. Apr 14 (forecast) |
| 'Flower buds visible' BBCH '51' | 1334 | '' est. Apr 14 (forecast) |
GDD = Growing Degree Days (base 32°F, Jan 1 start). Why base 32? GDD₃₂ thresholds from USA National Phenology Network citizen science observations (WA+OR). Season tracker for Kent / Auburn as of Apr 3, 2026. Predicted dates use 16-day weather forecast through Apr 19, 2026, then climate normals.