Biology and Management of Spotted Spurge (Euphorbia maculata) in Ornamental Crop Production and Landscapes

Class

Dicotyledonous plant

Family

Euphorbiaceae

Other Common Names

Milk-purslane and spotted sandmat

Life Span

This species is a summer annual that can persist almost year-round in central and south Florida. However, it dies with frost.

Plant Biology

Spotted spurge (Euphorbia maculata) flowers early, produces large amounts of seed with little to no dormancy, and thrives in poor, dry, well-drained soils. It germinates between 60°F and 100°F and is commonly found in sidewalk cracks, roadsides, and gardens (NC State Extension 2021).

Habitat

Spotted spurge is commonly found in disturbed soils such as garden beds, sidewalk cracks, and hardscapes, as well as in almost every area of nursery production (greenhouses, pots, roadways, aisles, ditches, etc.) (Figure 1). This species thrives in dry environments. It grows well in coarse soils like sand or gravel, but it can also establish itself in compacted and nutrient-poor soil. Optimal growth occurs under full sun, but it can persist in shaded areas.

Distribution

Spotted spurge is considered native throughout the continental United States, including Florida (USDA-NRCS 2024). It is a common weed in the eastern United States, expanding westward to North Dakota, Texas, California, and Oregon. Additionally, it is found in Canada, Mexico, Central America, South America, Japan, New Zealand, and Lebanon.

Growth Habitat

Spotted spurge has a prostrate growth habit, growing low on the ground (Figure 2). Its stems emerge from a single taproot and grow horizontally, creating a thick carpet that can span several feet in some cases. Spotted spurge can produce several thousand seeds from a single plant and can become difficult to eliminate entirely from landscapes and nurseries (Molinar et al. 2009).

Seedlings

The cotyledons are smooth (without hair), oval-shaped, green on the upper side, and reddish purple underneath. They grow on short stalks that are also reddish purple (Figure 3). The part of the stem below the cotyledons, known as the hypocotyl, is hairless and pink to maroon in color. Seedlings can begin to flower and produce large quantities of seeds within weeks of germination without a dormancy requirement (NC State Extension 2021).

Shoot

Leaves grow in opposite pairs along hairy pink-to-brown stems. They are dark green, oval-lance shaped (wider at the base and longer than it is wide), and about 1/6 to 2/3 of an inch (4 to 17 mm) long (Hodgson 2020). Many plants have a red spot in the middle of the upper leaf surface, but this marking is not always present (Mahr, n.d.). Shoots will emit a white milky sap when broken (Sholedice and Renz 2006).

Roots

Roots develop from a central point with a small taproot and a more noticeable fibrous root system (Landschoot et al. 2026). Stems spread outward in a roughly radial pattern, staying mostly flat against the soil surface. Although the stems grow out from the center, they do not root at the nodes.

Inflorescence

The flowers are tiny, are not very noticeable, and have no petals. They grow where the leaves meet the stem (Figure 4). Each flower cluster has several male flowers and one female flower, surrounded by white-to-pink, petal-like parts.

Fruit and Seeds

The plant can start producing seeds within a month of flowering under ideal conditions (Figure 5). The fruit is hairy and has three chambers, each with a small, wrinkled, light brown seed. One plant can produce thousands of seeds, which spread easily by sticking to animals, clothes, or tools. Irrigation water can also spread spotted spurge throughout nurseries if it is growing along ditches or irrigation ponds. Some seedlings may germinate almost immediately, while other seeds may survive and germinate the following season or when ideal conditions are met. Spotted spurge seeds will not germinate if they are buried too deep, as they require some sunlight for germination (Sidhu and Saha 2021).

Similar Species

There are over 20 species of Euphorbia in Florida. Spotted spurge (Euphorbia maculata) is often confused with prostrate spurge (Euphorbia prostrata) (Figure 6A), spreading sandmat (Euphorbia humistrata) (Figure 6B), and creeping spurge (Euphorbia serpens) (Figure 6C) because they all have prostrate-type growth habits and similar small leaves. However, E. maculata (Figure 6D) usually has longer, more pointed leaves with a distinct, dark red or purple spot near the center, while E. prostrata has shorter, rounder leaves and more noticeable reddish pigmentation along the stems. E. humistrata can be distinguished from E. maculata by its broader, egg-shaped to oval leaves with asymmetrical bases. Meanwhile, E. serpens has the roundest leaves of the group and slightly larger, though still tiny, flower structures. All four species can look alike at first glance, but differences in leaf shape, coloration, and flower size can help distinguish them.

Physical and Cultural Control

The most effective way to control spotted spurge in lawns is through consistent cultural practices that promote healthy turfgrass growth, such as proper watering, fertilizing, and mowing (Henderson and Patterson 2021). For more information on spurge control in turfgrass, see Ask IFAS publication ENH884, “Weed Management Guide for Florida Lawns.” Applying mulch in landscape beds or in nursery pots helps block sunlight, which reduces seed germination and seedling growth. For example, pine bark nuggets applied at a 1-inch depth reduced spotted spurge emergence by around 90% in a container study (Cregg and Schutzki 2009). Many different types of landscape mulch are available and can be suitable for spurge management, including wood chips, pine bark nuggets, and other organic materials. Related publications on mulch types and their uses can be found on the Ask IFAS topic page for mulches. In nurseries, many of these mulch materials are also effective for spurge control in containers; for example, parboiled rice hull mulch applied at a 1-inch depth has also been shown to significantly reduce spotted spurge emergence (Neal 2016). Minimizing soil disturbance and removing seedlings by hand before they go to seed are simple but effective ways to keep this weed under control. Combining all these methods creates an environment that naturally suppresses spurge and supports healthy plant growth.

Chemical Control