Amaranthus palmeri – Carelessweed

Amaranthus palmeri - Carelessweed, Palmer Amaranth, Palmer's Amaranth

Amaranthus palmeri - Carelessweed, Palmer Amaranth, Palmer's Amaranth

Plant Name

Scientific Name: Amaranthus palmeri

Common Names: Carelessweed, Palmer Amaranth, Palmer's Amaranth

Plant Characteristics

Duration: Annual

Growth Habit: Herb/Forb

Arizona Native Status: Native

Habitat: Desert, Upland, Riparian

Flower Color: Green

Flowering Season: Summer, Fall

Height: To 6 feet (1.8 m) tall, but usually less

Description: The flowers have 5 sepals and lanceolate, spine-tipped bracts. The flowers are both borne in the leaf axils and densely clustered on long, thin, often drooping terminal flower spikes. The central, terminal inflorescence is up to 18 inches (46 cm) long and is noticeably longer than the lateral flower spikes. The seeds are shiny, red-brown in color, and tiny, less than 1/16 inch (~1 mm) long. The leaves are simple, green, alternate, hairless, petiolate, egg-shaped to lance-shaped, and often variegated with a horizontal band of silver-green. The stems are erect, branched, and usually reddish in color.

These plants are often found growing in fields, along roadsides, in drainage areas, and along desert washes. The spine-tipped flower bracts are prickly (especially when dry) and can scratch bare skin. Do not walk through a dense patch of dried Carelessweed while wearing shorts.

Special Characteristics

Allergenic – The male flowers have highly allergenic pollen.

Edible – When cooked, the spinach-like leaves and small seeds are edible and nutritious. Birds and mammals also eat the plants and seeds. Warning: This plant can concentrate potentially harmful levels of nitrates in its leaves if grown in nitrogen-rich soil. Do not eat this plant if it's grown in fertilized soil or in soil that receives any agricultural runoff.


Kingdom: Plantae – Plants
Subkingdom: Tracheobionta – Vascular plants
Superdivision: Spermatophyta – Seed plants
Division: Magnoliophyta – Flowering plants
Class: Magnoliopsida – Dicotyledons
Subclass: Caryophyllidae
Order: Caryophyllales
Family: Amaranthaceae – Amaranth family
Genus: Amaranthus L. – pigweed
Species: Amaranthus palmeri S. Watson – carelessweed

More About This Plant

Arizona County Distribution Map
Carelessweed or Palmer Amaranth (Amaranthus palmeri)