annual

Hairy Beggar-Ticks

The Story

Plant Bio

Bidens pilosa is an erect annual or short-lived perennial herb native to tropical and subtropical America, reaching heights of twelve to forty inches. The opposite leaves are primarily trifoliate or pinnate with toothed margins, supported by stems that range from smooth to densely hairy.

The plant produces small flower heads containing tubular yellow disk florets, which are either completely rayless or bordered by tiny, short-lived white rays. Each flower head matures into dozens of four-angled, barbed seeds that aggressively cling to passing animals and clothing.

Uses & Benefits:

None; the small, often rayless flower heads lack significant visual appeal.

Acts as a rapid colonizer of disturbed, eroded soils, though its weed status outweighs this utility.

Provides pollen and nectar for generalist insects and bees, and seeds for some seed-eating birds.

Essentials

At a Glance

Plant Type

Annual

Height

40"

Width

24"

Light

Full Sun, Partial Sun

Zones

8, 9, 10

Water

Low to Moderate

Humidity

High

Lifespan

Annual or short-lived perennial

Native To

Tropical and Subtropical America

Toxicity

Non-toxic but causes mechanical irritation from barbed seeds

Bloom period

Summer – Fall

In flower about 6 months of the year

Planting

How to Grow

Identify seedlings in spring by their opposite, toothed, trifoliate leaves and erect, square stems.
Hand-pull young plants from moist soil before the taproot establishes deeply.
Cut back mature stands to ground level before flower buds open to disrupt the seed cycle.
Dispose of cleared plants securely in sealed bags rather than composting to prevent seed survival.

Pro Tip

Mow or hand-pull plants before the yellow flower heads fade to prevent the development of the barbed, self-dispersing seeds.

Keep It Thriving

Care Guide

Do

Monitor disturbed soil and garden edges regularly for emerging seedlings.
Wear thick gloves and protective clothing when clearing mature plants to avoid skin punctures from the barbed seeds.
Bag and discard all flowering stems immediately after cutting.

Don't

Do not allow flower heads to mature and set seed in cultivated garden beds.
Do not add seed-bearing stems to home compost piles where temperatures fail to destroy the seeds.
Do not apply supplemental fertilizer, which only triggers rapid, rank weed growth.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Pest Check
Prune
Spring Cleanup
Winter Prep

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

None (treated as an invasive weed)Soil stabilization in highly disturbed, degraded waste areas

Multiply

Propagation Methods

Good to Know

Common Questions

Hairy Beggar-Ticks questions

What zones can Hairy Beggar-Ticks grow in?

Hairy Beggar-Ticks is hardy in USDA Zones 8–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Hairy Beggar-Ticks deer resistant?

Yes — Hairy Beggar-Ticks is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does Hairy Beggar-Ticks bloom?

Hairy Beggar-Ticks typically blooms in summer through fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Hairy Beggar-Ticks need full sun?

Hairy Beggar-Ticks does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is Hairy Beggar-Ticks drought tolerant?

Yes — once established (usually after the first full season), Hairy Beggar-Ticks handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.