Common Ragweed
Scientific Name: Ambrosia artemisiifolia
Plant Family: Asteraceae
Native Region: North America; now widely naturalized in Europe and Asia
Brief Description
An annual weed known for its deeply lobed, fern-like leaves and inconspicuous green flower spikes. It has a branched, hairy stem and causes significant seasonal allergies.
Care Instructions
Generally considered a weed, it requires no care. It thrives in disturbed soils, needs full sun, and is highly drought-tolerant. Control involves pulling before it sets seed.
Medicinal Value
We do not currently provide medicinal value for plant identifications.
Sunlight
Full sun, requiring at least 6 to 8 hours of direct light daily.
Watering
Low to moderate; highly drought-tolerant once established but grows more vigorously with regular moisture.
Soil
Adaptable to most soil types including sandy, loamy, and clay; prefers slightly acidic to neutral pH (6.0-7.0).
Hardiness Zone
3-11 (Annual)
Growth Habit
Summer annual herb; upright growth reaching 1 to 5 feet in height; fast growth rate.
Bloom Season
Late summer to autumn (August-October); produces small, yellow-green inconspicuous flowers on terminal spikes.
Toxicity
Non-toxic to ingest for most mammals, but its pollen is a primary cause of hay fever in humans. Some people may develop contact dermatitis from handling the leaves.
Propagation
Mainly by seed; a single plant can produce up to 60,000 seeds that remain viable in the soil for decades.
Common Pests & Issues
Susceptible to ragweed leaf beetles (Zygogramma suturalis) and various rust fungi, which are sometimes used for biological control.
Similar Species
Mugwort (Artemisia vulgaris) which has silver undersides on leaves, and Marigolds (Tagetes) which have distinct floral scents and showy flowers.
Interesting Facts
A single ragweed plant can release a billion pollen grains in one season, which can travel hundreds of miles over the ocean and up to two miles into the atmosphere.
Created At: 2026-05-13T14:09:00.898133