annualN. America Native

Redroot Pigweed

The Story

Plant Bio

Amaranthus retroflexus, commonly known as redroot pigweed, is a coarse, erect summer annual native to central and eastern North America. It features dull green, lanceolate to ovate leaves with prominent whitish veins and a stout, branching habit that thrives in disturbed soils.

This species is distinguished by its dense, stiff, spikelike green panicles of tiny, wind-pollinated flowers and its characteristic reddish taproot. Young foliage often exhibits purplish undersides, but the mature plant quickly becomes tough and spinescent.

Uses & Benefits:

This plant has no ornamental value and is generally considered an unsightly agricultural weed.

Young leaves are historically used as a potherb, and the seeds can be harvested and ground into flour.

The abundant seeds provide a valuable food source for ground-feeding songbirds and game birds in autumn.

Essentials

At a Glance

Plant Type

Annual

Height

72"

Width

24"

Light

Full Sun

Zones

4, 5, 6, 7, 8, 9, 10

Water

Low

Humidity

Moderate

Lifespan

Annual

Native To

North America

Toxicity

Toxic to Livestock

Bloom period

Summer – Fall

In flower about 6 months of the year

Planting

How to Grow

Select a site in full sun with well-drained soil, as this species strictly requires direct sunlight and does not tolerate shade.
Avoid applying fertilizers or supplemental water, as the plant thrives aggressively on nutrient-rich, disturbed ground and possesses high drought tolerance.
Monitor the area for the emergence of young, dull green leaves with wavy margins and fine hairs on the undersides.
Uproot the entire plant, including the red taproot, before the green flower spikes mature and release seeds.

Pro Tip

Rogue out plants immediately upon detection before they set seed; a single specimen can produce tens of thousands of highly viable seeds that persist in the soil seedbank for up to forty years.

Keep It Thriving

Care Guide

Do

Pull young plants manually while the soil is moist to ensure the entire taproot is removed.
Dispose of uprooted flowering specimens in sealed waste bags rather than composting them to prevent seed dispersal.
Wear gloves when handling mature flower spikes, as the stiff bracts can be somewhat sharp.

Don't

Do not allow the plant to flower and set seed, as the seeds remain viable in the soil for decades.
Do not apply nitrogen fertilizers, which only fuel aggressive, weedy growth and increase nitrate accumulation.
Do not feed mature foliage to livestock, as it accumulates toxic levels of nitrates and oxalates.

Seasonal Care Calendar

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

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Foraging GardensEthnobotanical DisplaysWildlife Cover

Companion Plants

Gomphrena globosa Bouteloua dactyloides Schizachyrium scoparium

Multiply

Propagation Methods

Good to Know

Common Questions

Redroot Pigweed questions

What zones can Redroot Pigweed grow in?

Redroot Pigweed is hardy in USDA Zones 4–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Redroot Pigweed deer resistant?

Not reliably. Deer may browse Redroot Pigweed, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Redroot Pigweed bloom?

Redroot Pigweed 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 Redroot Pigweed need full sun?

Redroot Pigweed does best in full sun (6+ hours).

Is Redroot Pigweed drought tolerant?

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