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whitethorn ceanothus

Ceanothus cordulatus Β· Rhamnaceae

whitethorn ceanothus (Ceanothus cordulatus)
Photo: (c) Justin, some rights reserved (CC BY) Β· CC BY Β· via iNaturalist

whitethorn ceanothus (Ceanothus cordulatus) is a perennial shrub in the Rhamnaceae family. It is native to North America. USDA records it as hardy in zone 4 and warmer, down to about -23Β°F.

At a glance

Typeshrub USDA
Lifecycleperennial USDA
Native statusnative USDA
Mature height8 ft USDA
Lightpart-shade USDA
Water needlow USDA
Growth rateslow USDA
Soil pH7–8.5 USDA
BloomJune USDA
Flower colorWhite USDA
Hardiness zones4 and warmer USDA
Guild layershrub Derived
Nursery availabilityRoutinely Available USDA

USDA quoted from the USDA PLANTS database Β· Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It grows in partial shade. USDA rates it as having low water needs once established. It is recorded on soils from pH 7 to 8.5 β€” a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 4; USDA publishes no warm-end limit, so gardeners in warmer zones should check local heat tolerance separately.

Size and growth

At maturity it reaches about 8 ft, making it a mid-sized plant. It grows slowly, which matters when you are timing a planting around the layers above it.

Bloom period

USDA records a bloom period of June. The flower color USDA records is white. Bloom timing is how the Guild Builder overlaps flowering across a planting so something is in flower for as much of the season as possible.

Bloom period is a claim about when this plant flowers. It is deliberately not a pollinator rating β€” no dataset we trust publishes one, so we do not make that claim. See Data & sources.

Role in a guild

Shrub layer. In a layered planting this is woody mid-level structure between the understory and the ground. We derive the layer from the plant's growth habit and mature height using a fixed rule, so the same inputs always produce the same layer.

Build a guild around whitethorn ceanothus β†’

Tags

deciduoussandy-soilnativenitrogen-fixerdrought-tolerantslow-growing

Related plants

Others in Ceanothus

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol CECO, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

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