Pacific Madrone
Arbutus menziesii
Ericaceae · broadleaf evergreen tree · native
Last updated
This profile synthesizes data from multiple published sources. Expert field review is in progress.
Pacific madrone is the tree that defines whether you understand Puget Sound horticulture or just think you do. The rules are simple and absolute: do not transplant anything taller than about 12 inches, do not irrigate established trees, and do not amend the soil. Madrone needs sharply drained, acidic to neutral ground and will rot in any soil that holds water, whether valley clay or till over hardpan. The species is restricted to zones 8a-8b with a narrow coastal distribution. Ten diseases are documented, mostly leaf spots and cankers that are cosmetic on healthy trees but lethal on stressed ones. The bark exfoliates constantly; the litter is significant. If your site has existing madrones, the best management is to leave them alone. If you want to plant one, start small, plant in fall, mulch with its own leaf litter, and accept that it will grow slowly (25 feet in 20 years).
— Chris Welch, ISA Certified Arborist
Arbutus menziesii (Ericaceae) is a slow-growing broadleaf evergreen tree native to a narrow coastal belt from British Columbia to southern California. It reaches 80 feet at maturity (about 25 feet in 20 years), forming a rounded crown with a characteristically twisted, sculptural trunk. The smooth, exfoliating bark reveals reddish-brown to orange surfaces beneath, making it one of the most visually striking native trees in its range. Leathery, dark green leaves are coarse-textured and persistent. Small white urn-shaped flowers (about 1 cm) appear in terminal clusters from April to May, followed by red berry-like fruits that attract birds.
Pacific madrone requires full sun to part shade on well-drained, acidic to slightly acidic soil (pH 4.5 to 7.4) with low water needs once established. Drought tolerance is high, and the species resprouts after top damage. It has low calcium carbonate tolerance and needs a minimum root depth of about 24 inches. Transplanting is notoriously difficult; root disease (particularly Phytophthora) and transplant shock cause high mortality in nursery-grown stock. The profile documents 10 diseases and 4 pests. Fruit is edible (rated 3 out of 5) with some medicinal use. Hardy in Zones 8a to 8b.
Quick Facts
Phenological Calendar
As of April 23, 2026, Puget Sound stations range from 1434.4 to 1592.7 GDD₃₂. Pacific Madrone has passed 'first bloom' (1327 GDD₃₂).
Regional Season Tracker
GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 23, 2026| Station | GDD₃₂ | Current Stage | Next | To Go |
|---|---|---|---|---|
| Issaquah / East King | 1,593 | 'First bloom' | — | — |
| Seattle / UW | 1,554 | 'First bloom' | — | — |
| Kent / Auburn | 1,537 | 'First bloom' | — | — |
| Olympia / Tumwater | 1,505 | 'First bloom' | — | — |
| Bellingham / Whatcom | 1,483 | 'First bloom' | — | — |
| Tacoma / Puyallup | 1,472 | 'First bloom' | — | — |
| Sequim / Rain Shadow | 1,434 | 'First bloom' | — | — |
| Stage | GDD32 | Typical Window |
|---|---|---|
| 'Flower buds visible' BBCH '51' | 926 | '' |
| 'Bud break' BBCH '07' | 1327 | '' |
| ● 'First bloom' BBCH '61' NOW | 1327 | '' |
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 23, 2026. Predicted dates use 16-day weather forecast through May 10, 2026, then climate normals.