Ambrosia Species, Buffaloweed, Giant Ragweed, Great Ragweed, Horseweed, Palmate Ragweed
Ambrosiatrifida

Family: Asteraceae (ass-ter-AY-see-ee)
Genus: Ambrosia (am-BRO-zhuh)
Species: trifida (TRY-fee-duh)

Synonym:Ambrosia trifida var. trifida

Category
Annuals

Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater

Sun Exposure
Full Sun

Foliage
Herbaceous

Foliage Color

Height
6-8 ft. (1.8-2.4 m)
8-10 ft. (2.4-3 m)
10-12 ft. (3-3.6 m)
12-15 ft. (3.6-4.7 m)

Spacing
24-36 in. (60-90 cm)

Hardiness
Not Applicable

Where to Grow

Danger
Handling plant may cause skin irritation or allergic reaction
Pollen may cause allergic reaction

Bloom Color
Chartreuse (yellow-green)
Inconspicuous/none

Bloom Characteristics

Bloom Size

Bloom Time
Mid Summer
Late Summer/Early Fall

Other details
May be a noxious weed or invasive

Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)

Patent Information
Non-patented

Propagation Methods
From seed; direct sow outdoors in fall
From seed; stratify if sowing indoors
Scarify seed before sowing

Seed Collecting
Bag seedheads to capture ripening seed
Properly cleaned, seed can be successfully stored