1 / 12

Pedicularis sylvatica

common lousewort

Orobanchaceae Western and central Europe

Attracts Pollinators

SunFull Sun – Part Shade

WaterHigh

HardinessZones 4–7

Overview

Pedicularis sylvatica is a low, hemiparasitic perennial 2-10 inches (5-25 cm) tall that draws part of its nutrition from the roots of nearby grasses and sedges. It forms a low spread of branching, often reddish stems carrying fern-like leaves cut into many small, toothed lobes. From late spring through summer it bears two-lipped pink flowers about 0.8-1 inch (20-25 mm) long, the upper lip hooded and the lower lip three-lobed, held in loose leafy spikes. The inflated, ribbed calyx behind each flower is a clear field mark. It grows on damp, acidic, nutrient-poor ground such as wet heath, bog margins, marshy grassland, and flushes, and depends on suitable host plants nearby to grow well. Because of its partial parasitism it is difficult to grow away from a natural community and rarely persists in ordinary cultivated soil. The plant is small and easily lost among taller vegetation, and it declines when its damp habitats are drained or enriched. It is pollinated mainly by bumblebees, which work the hooded flowers.

Native Range

Pedicularis sylvatica is native to western and central Europe, from the British Isles and Scandinavia south to Iberia and Italy. It grows in damp, acidic heath, bog margins, and poor wet grassland.

Suggested Uses

Found in conservation and naturalistic plantings of wet heath, bog, and acid grassland rather than in formal borders. Where its habitat and host plants exist, it adds early-summer pink colour to low, damp swards.

How to Identify

Recognise it by the low rosette of fern-like, deeply cut leaves and the loose spikes of large pink two-lipped flowers in late spring and summer. The inflated, sharply ribbed calyx behind each bloom and the often reddish stems are reliable field marks. It occurs only on damp, acidic, low-nutrient ground, which separates it from pink-flowered plants of richer soils.

Appearance

Size & Dimensions

Height2" - 10"

Width/Spread4" - 10"

Colors

Flower Colors

pink

Foliage Colors

green

Bloom Information

Bloom Period

~12 weeks

Spring Summer

Pink two-lipped flowers open from April to July, a few at a time up short leafy spikes. The long flowering spell suits the bumblebees that pollinate it. Inflated seed calyces follow and persist as the flowers fade.

Detailed Descriptions

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 4-10 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range4.0 - 6.0(Acidic)

357912

Soil Types

peat sand loam

Drainagemoist

Water & Climate

Water Needs

High

Frost Tolerance

hardy

Time to Maturity

Slow; depends on host establishment

Care & Maintenance

Care Guide

This hemiparasite is difficult in cultivation and grows reliably only within an established community of grasses or sedges that act as hosts on damp, acidic, lime-free soil. Full sun to light shade and steady moisture through the growing season suit it, while drying or enrichment of the ground causes decline. It will not establish in rich, cultivated borders or in containers without host roots. No feeding is given, since the plant is adapted to nutrient-poor sites. Seed needs cool, damp, open ground and nearby hosts to establish. Once settled in the right habitat it needs no routine care.

Pruning

No pruning is needed for this small perennial. Spent flower spikes are left so the inflated seed capsules can ripen and shed seed into the surrounding turf. Top growth dies back in winter and returns from the rootstock.