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Canadian lousewort

Pedicularis canadensis · Scrophulariaceae

Canadian lousewort (Pedicularis canadensis)
Photo: Wikimedia Commons · Public domain · via Wikimedia Commons

Canadian lousewort (Pedicularis canadensis) is a perennial herbaceous plant in the Scrophulariaceae family. It is native to North America. USDA records it as hardy in zone 2 and warmer, down to about -43°F.

At a glance

Typeforb-herb Derived
Lifecycleperennial USDA
Native statusnative USDA
Mature height1.3 ft USDA
Lightshade USDA
Water needmedium USDA
Growth ratemoderate USDA
Soil pH4–7 USDA
BloomMay–June USDA
Flower colorYellow USDA
Hardiness zones2 and warmer USDA
Guild layerground-cover Derived
Nursery availabilityNo Known Source USDA

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

Growing conditions

It tolerates full shade. USDA rates it as having moderate water needs. Its drought tolerance is rated low. It will not tolerate waterlogged soil — USDA rates its anaerobic tolerance as none. It is recorded on soils from pH 4 to 7 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 2.

Size and growth

At maturity it reaches about 1.3 ft, making it a low, mat-forming plant. It grows at a moderate rate.

Bloom period

USDA records a bloom period of May through June. Flowers are yellow.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is gray-green, fine in texture. Its flowers are conspicuous. Its active growth period is spring and summer. USDA rates its lifespan as moderate.

What the site needs to provide

USDA records it across sites receiving 34 to 60 inches of annual precipitation. It needs at least 120 frost-free days to finish its season. It roots to at least 6 inches. Fertility requirement: medium.

Propagating it

Propagate it from seed and bare root. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a slow rate. It does not spread vegetatively, so it will stay where you put it.

Resilience and wildlife

Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated medium. Its growth form is recorded as single stem.

Role in a guild

Ground cover. In a layered planting this is the lowest layer — it shades soil, holds moisture, and suppresses weeds. The layer is derived by a fixed rule from growth habit and mature height.

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Tags

deciduousclay-tolerantdeer-resistantnativeshade-tolerantground-cover

Related plants

Others in Pedicularis

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol PECA, 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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