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Asthma Plant

Euphorbia hirta (yoo-FOR-bee-uh HER-tuh)

Family: Euphorbiaceae Native Herbaceous (1-3 ft)

Garden spurge is an herbaceous annual plant considered to be a warm-season weed in the spurge family (Euphorbiaceae). It originates from tropical and subtropical Americas but has spread to Africa, Southeast Asia, the Pacific Islands, and Australia. It is found in lawns, agricultural areas, roadsides and in the nursery trade. It can also be found in planting beds, sidewalk cracks, or between patio pavers. The specific epithet, hirta , is Latin for hairy and references the plants stems. This plant can grow in full sun to full shade. It tolerates most growing conditions including poor soils. It can grow in almost any type of soil and grows rapidly. It does require moderate amounts of water and well-drained soil. Garden spurge is intolerant to frost, but it serves as annual in temperate areas that have warm or hot summers. Each plant can produce thousands of seeds over the growing season. Several thousand seeds can be produced by one plant over 2 to 3 months. The stems are round, reddish-purple and covered with long yellowish-brown hairs and short white hairs. The stems grow 6 to 20 inches in length and are prostrate to ascending. The leaves are opposite, oblong to lanceolate with a pointed tip, and green with a reddish to purplish coloring. The tiny flowers are produced in small clusters in the leaf axils and are green to brown to pinkish in color. The fruits are a 3-lobed capsule and contain reddish-brown seeds. The seeds have no dormancy period and germinate once they are dispersed by the wind or water. Garden spurge could be used as a ground cover, bed border, or container planting, if desired. Insects, Diseases, and Other Plant Problems: Monitor for aphids, mealybugs, and spider mites.Fungal diseases such as powdery mildew can occur. This plant can be weedy and may be controlled by hoeing or hand pulling. Mulch will help prevent seeds from germinating as they need light to do so. Chemical control can be done with most postemergence herbicides and systemic herbicides such as glyphosate. As with most euphorbias, the stems contain a milky sap that may cause contact dermatitis. Wear protective gloves when handling this plant. All parts of this plant are toxic, if ingested. Monitor small children and pets in the presence of this plant. VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti," a plant identification course offered in partnership with Longwood Gardens. More information on Euphorbia .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 64 attributes.

How it fits the guild

Guild layer 4 - Herbaceous (1-3 ft)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Euphorbia hyssopifolia Euphorbia maculata Euphorbia nutans
Fills a similar niche Euphorbia hyssopifolia Euphorbia maculata Euphorbia serpens

Full plant profile

Growing Conditions
Plant type
Annual; Native Plant; Perennial; Poisonous; Weed
Life cycle
Annual
Light
Deep shade (Less than 2 hours to no direct sunlight) | Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand; Shallow Rocky
Soil drainage
Good Drainage | Moist | Occasionally Dry
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 0 ft. 6 in. - 1 ft. 0 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Rapid
Maintenance
High
Canopy layer
4 - Herbaceous (1-3 ft)
Form & Appearance
Habit / form
Ascending; Erect; Prostrate
Texture
Medium
Leaf color
Green; Purple/Lavender; Red/Burgundy
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Oblong
Leaf margin
Serrate
Leaf feel
Glossy; Smooth
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
No
Leaf detail
Green leaves may have reddish-purple spots and measure 0.5 to 1.5 inches long. They have a pointed tip, serrated margins and are oblong to lanceolate in shape. If the plants are grown in poor soil the leaf color becomes red.
Flower color
Cream/Tan; Green; Pink
Flower form
Insignificant
Flower shape
Irregular
Flower size
< 1 inch
Flower detail
The tiny flowers have no petals and occur in ball-shaped clusters (Cyathia) in the leaf axils. Reduced, bract-like leaves occur under the inflorescences. The flower cluster measures 0.2 to 0.4 inches in diameter and is tan to greenish to pink.
Bloom time
Fall; Summer
Fruit color
Gold/Yellow
Fruit type
Capsule
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Fruit is a 3-lobed capsule that is hairy and yellowish and measures 0.08 by 0.06 inches. Fruits from a single plant can produce up to 3000 tiny, oblong, four-sided, reddish-brown seeds. The capsules dry and dehisce to disperse the seeds.
Stem color
Purple/Lavender; Red/Burgundy
Stem detail
The reddish-purplish stems are round and densely covered with long yellowish-brown hairs and short white hairs. They are prostrate to ascending and can measure 6 to 20 inches long. The stems are filled with a milky white latex sap.
Wildlife & Ecology
Native status
Native
Origin
Tropical and Subtropical Americas
Distribution
Native: United States--Al, AZ, CA, FL, GA, LA, MS, NV, NM, NC, SC, TX, and UT; Argentina, Aruba, Bahamas, Belize, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Guatemala, haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Paraguay, Peru, Puerto Rico, and Venezuela; Introduced: United States--AR, HI, MD, NY, and WI; Angola, Bangladesh, Bermuda, Botswana, Cambodia, Cameroon, Cape Verde, Central African Republic, Chad, China, Cyprus, Egypt, Ethiopia, Fiji, Gabon, Gambia, Gabon, India, Japan, Kenya, Liberia, Libya, Madagascar, Morocco, South Wales, New Zealand North, Nigeria, Pakistan, Palestine, Queensland, Rwanda, Samoa, Saudi Arabia, Sudan, Taiwan, Tanzania, Thailand, Tonga, Vietnam, West Himalaya, Western Australia, Zambia, Zaire, and Zimbabwe.
Play value
Easy to Grow
Food & Medicine
Edible parts
Leaves
Harvest time
Fall; Summer
Fruit type
Capsule

Edibility

Herbal teas can be made from the leaves

Uses (ethnobotany)

Traditional medicinal herb in some tropical countries.

Landscape Use
Landscape location
Container
Design feature
Border
Garden tags
#green flowers #sap #weed control #milky sap #white flowers #full sun tolerant #seedheads #summer annual weed #groundcover #bright green #fall interest #warm season weed #fast growing #summer flowers #warm climates #annual #high maintenance #problem for children #problem for dogs #poisonous #problem for cats #weedy #contact dermatitis #poisonous if ingested #NC native #native annual
Problems & Resistance
Problems
Contact Dermatitis; Poisonous to Humans; Problem for Cats; Problem for Children; Problem for Dogs; Weedy
Resistant to
Compaction; Drought; Dry Soil; Poor Soil
Propagation
Seed; Stem Cutting
Poison severity
Low
Poison parts
Flowers; Fruits; Leaves; Sap/Juice; Seeds; Stems
Poison symptoms
The milky white latex sap in all plant parts can cause mild to severe contact dermatitis. If contact with the eyes occurs the sap can cause temporary to permanent damage to the cornea. If eaten, blistering can occur on lips and oral mucosa. Avoid ingesting plant parts and keep plants away from pets and children.
Toxic principle
Diterpene esters in milky latex
Contact dermatitis
Yes
Toxicity summary
Low severity poison; parts: Flowers; Fruits; Leaves; Sap/Juice; Seeds; Stems; contact dermatitis

Planted at Hunnicutt

Nobody’s planted this one yet.