The term "chickweed" most notably describes Common Chickweed (Stellaria media), although there are several other chickweeds, all in the genus Stellaria.
Common Chickweed is a cool weather plant native to Europe that has widely naturalized in the United States and throughout the world. It’s often found in lawns and other areas of shady, moist soil.
Depending on climate, chickweed normally appears during the cooler temperatures of fall and dies back in the late spring or early summer heat. It thrives between 53° and 68°F.