What are the sun requirements for Galium aparine?

Galium aparine requires Part Shade.

How much water does Galium aparine need?

Galium aparine has Medium water needs.

Perennials

Galium aparine

cleavers (native)

Rubiaceae

Circumboreal; native to both North America and Eurasia

At a Glance

TypeAnnual

HabitClimbing

FoliageDeciduous

Height12-60 inches (30-150 cm)

Width12-36 inches (30-90 cm)

Key Features

Native to North America

Maintenancemoderate

Overview

Galium aparine is a scrambling, clinging winter annual in the coffee family (Rubiaceae) reaching 12–60 inches (30–150 cm) in length with a 12–36 inch (30–90 cm) spread. Stems are square in cross-section, weak, and unable to support themselves; they climb over adjacent vegetation and structures using tiny recurved hooks (retrorse prickles) along the stem angles and leaf margins. Leaves are linear to oblanceolate, 0.5–2 inches (1–5 cm) long, in whorls of 6–8 at each node. Flowers are tiny, white, four-petaled, 0.04–0.08 inch (1–2 mm) across, borne in small axillary clusters. Fruit is a pair of globose nutlets 0.1–0.15 inch (2.5–4 mm) in diameter, densely covered in hooked bristles that adhere to animal fur, feathers, and clothing. A single plant produces 100–400 seeds. Seeds germinate primarily in fall, forming winter rosettes that bolt and climb rapidly in spring. The hooked bristles on all surfaces are the defining tactile feature; pulling a stem through fingers reveals the clinging texture. Naturalized as a weed in gardens, hedgerows, and cultivated ground throughout temperate regions.

Native Range

Circumboreal distribution: native to both North America and Eurasia, occurring in moist, partially shaded habitats including woodland edges, hedgerows, streambanks, gardens, and cultivated fields from sea level to approximately 7,000 feet (2,100 m). Found across all 50 U.S. states, all Canadian provinces, and throughout Europe and Asia.

Suggested Uses

Used in weed identification courses for teaching Rubiaceae whorled-leaf morphology and adhesive seed dispersal mechanisms. The clinging hooks are used as a teaching example of passive animal dispersal (epizoochory). Historically used as a coffee substitute (roasted seeds) and as a spring potherb. Seeds consumed by ground-feeding birds.

How to Identify

Identified by the whorled leaves (6–8 per node), square stems covered in tiny recurved hooks, and the clinging, scrambling habit. Distinguished from Galium trifidum (small bedstraw) by the larger whorls of 6–8 leaves versus 4, the larger overall size, and the hooked fruit versus smooth fruit. Distinguished from Galium mollugo (smooth bedstraw) by the annual habit, the hooks on stems and fruit, and the fewer flowers per cluster. Running a stem through fingers reveals the characteristic Velcro-like clinging sensation.

Appearance

Size & Dimensions

Height1' - 5'

Width/Spread1' - 3'

Colors

Flower Colors

white

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Bloom Period

~8 weeks

SpringSummer

Flowers from April through July. Individual flowers open for 1–2 days. Small clusters of 1–3 flowers in leaf axils bloom sequentially along the elongating stems over 6–8 weeks. Self-pollinating. Hooked fruits mature 2–3 weeks after flowering and adhere to passing animals and clothing for dispersal. In the Pacific Northwest, flowering peaks in May through June.

Detailed Descriptions

Foliage Description

Medium green, linear to oblanceolate, in whorls of 6-8 at each node; covered in tiny recurved hooks

Growing Conditions

Sun Requirements

Partial Shade

Full Sun

Requires 3-8 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 Range5.5 - 7.5(Neutral)

357912

Soil Types

loamclaysilt

Drainage

moist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Care & Maintenance

Care Guide

Hand-pulling before flowering and seed set is effective; the shallow root system extracts easily from moist soil. The clinging hooks make pulling in tangled vegetation time-consuming, as stems break and adhere to adjacent plants. Pulling is most efficient when stems are short in late winter through early spring before they climb into adjacent vegetation. Hoeing at the seedling rosette stage in fall or early spring prevents bolting. Dense mulching with 2–3 inches (5–8 cm) of organic material suppresses fall germination. The hooked fruit sticks to gloves, clothing, and tools, facilitating inadvertent dispersal during garden work.

Pruning

No pruning applicable. Plants are removed by pulling before fruit matures. Stems break easily; thorough removal of all vegetative material reduces seed production. The hooked fruit disperses readily on clothing and equipment during removal.

Maintenance Level

moderate

⚠️ Toxicity Warning

Non-toxic