Spurge is an annual broadleaf weed that quickly colonizes thin or stressed turfgrass. This fast-growing, mat-forming nuisance thrives in dry, sunny, and often compacted soil where healthy grass struggles. The weed produces thousands of seeds from a single plant, ensuring rapid spread throughout the warm season. This guide details how to identify spurge, offering immediate removal techniques, chemical control options, and long-term cultural practices to eliminate it permanently.
Confirming the Presence of Spurge
Spurge has a distinctive, low-growing, prostrate habit, radiating outward from a central taproot to form dense mats. The leaves are small, typically less than half an inch long, and are arranged oppositely along reddish, hairy stems. A defining characteristic is the milky white sap, or latex, that exudes when a stem or leaf is broken; this sap can be an irritant to the skin or eyes. Two common types are spotted spurge (Euphorbia maculata) and prostrate spurge (Euphorbia humistrata). Spotted spurge often displays a maroon spot in the center of its leaves, a feature sometimes absent in prostrate spurge. Both are summer annuals that germinate in warm soil and produce seeds quickly, making early identification important for control.
Targeted Physical and Non-Chemical Removal
For small, isolated patches, physical removal is the most direct way to eliminate spurge without chemicals. Successful manual removal requires extracting the entire taproot, which is easier when the soil is moist after rain or deep watering. Pull the plant firmly and slowly from the center; leaving any part of the root behind allows the plant to regenerate. An alternative non-chemical method involves localized spot treatments. Boiling water, poured carefully onto the plant, instantly damages the tissue and is effective for weeds in cracks or driveways. Horticultural vinegar (up to 20% acetic acid) can also be sprayed to burn the top growth. Be aware that these non-selective treatments will kill surrounding turfgrass and primarily target foliage, meaning persistent taproots may require repeated applications.
Selecting the Right Herbicides for Control
Chemical control is the most effective solution for widespread infestations, typically requiring a dual-approach strategy using pre-emergent and post-emergent herbicides. Pre-emergent herbicides stop spurge seeds from germinating and should be applied in early spring before soil temperatures consistently reach 60 to 70 degrees Fahrenheit. Effective active ingredients include prodiamine, dithiopyr, or pendimethalin. Applying a pre-emergent creates a chemical barrier at the soil surface. This application requires watering in (about a half-inch of irrigation) to activate the barrier. For established spurge plants that have already emerged, a post-emergent herbicide is necessary. These selective broadleaf weed killers often contain active ingredients like 2,4-D, dicamba, MCPP (mecoprop), or triclopyr, frequently combined to target a wider range of weeds. Post-emergent products should be applied when the weeds are small and actively growing, ensuring the spray covers the foliage without significant runoff.
Cultural Practices to Prevent Future Growth
The most sustainable way to prevent spurge from returning is to cultivate a dense, healthy lawn that naturally crowds out weed growth. Spurge thrives where there is low competition for light and moisture, so altering lawn care practices is essential. Mowing your turf at a higher setting, typically between 3 and 3.5 inches, is a primary adjustment. Taller grass blades create shade, cooling the soil surface and blocking the sunlight needed for spurge seeds to germinate. Proper watering also plays a role; deep, infrequent irrigation encourages the grass to develop a deep root system. Aim to deliver about one inch of water per week, allowing the soil to dry slightly between waterings, which is unfavorable for shallow-rooted weeds. Furthermore, reducing soil compaction through regular core aeration allows grass roots to penetrate deeper, improving water and nutrient movement, and creating a hostile environment for spurge.