For years I’ve been dealing with a weed that appears every summer during the hottest time of the year. I’ve pulled it, hoed it and sprayed it but I never knew what it was. Now I do – spotted spurge (Euphorbia maculata).
I was fascinated when I found out that this weed is a Euphorbia. The genus Euphorbia is a strange and diverse group of plants that includes the crown of thorns house plant (Euphorbia milii), a number of different succulent species and, most surprising of all, the poinsettia (Euphorbia pulcherrima). One of the characteristics of a Euphorbia is that if you cut the stems, they exude a milky sap. This is one way to help identify spotted spurge – break a stem and you’ll see the sap.
Spotted spurge is a summer annual that grows in a prostrate manner and forms a mat that can reach the size of a dinner plate. The small leaves are opposite one another and oblong in shape with a maroon blotch on them. A closely related and very similar weed is prostrate spurge (Euphorbia humistrata). The primary difference between the two is that prostrate spurge will develop roots along its stems; spotted spurge does not.
I consider this weed to be a master of camouflage. The plants are difficult to detect when they’re small, especially if they’re growing on bark or stone mulch. The bad news is that spotted spurge starts to set seed when the plants are only a couple of weeks old. So all of those little plants that are overlooked until they get big have more than enough time to set a lot of seeds. No wonder this weed just keeps coming back year after year.
The good news is that spotted spurge is easy to control. The plant has a shallow root system and, since it doesn’t root along the stems, it’s very easy to remove by simply pulling the plant out of the ground.
Spotted spurge is one of those weeds about which I can’t get too concerned. It’s an annual so it dies with the first frost; it’s not noxious; it’s not terribly invasive and it’s easy to pull. I wish all weeds were like the spotted spurge!