PPDL Picture of the Week
March 29, 2021
Do you have Wild Onion in your lawn? Or possibly the Star-of-Bethlehem??
Glenn Hardebeck, Turfgrass Research Agronomist, Purdue University
Initially field identified as wild onion, this weedy
grass-like plant was received during the first week of March for an ID
confirmation. Wild onion is common
across the state and is currently showing itself quite well in turf areas, but
in this case, the sample turned out to be Star-of-Bethlehem. Star-of-Bethlehem is often mistaken for wild
onion or even some type of grass early after it emerges due to its narrow,
thick, up-right leaves. It develops from
a shallow bulb which readily distinguishes it from grasses, but this
characteristic is very similar to wild onion.
To distinguish between wild onion and Star-of-Bethlehem before flower
formation, a closer examination of the leaves is in order. The leaves of wild onions roll together to
form a closed straw-like structure that is hollow on the inside just like our familiar
green onion. Within a few days of
emergence, Star-of-Bethlehem leaves begin to form a roughly “U” shape with a
light-green to white line down the center inside the “U”. Within a couple of weeks the
Star-of-Bethlehem will form a white flower with six petals.
Unfortunately, the Star-of-Bethlehem is difficult to
control. Herbicides have little
effect. Some intense homeowners have had
a measure of success pulling the plants being sure to remove the bulbs as
well. For most of us, it is likely better
to increase our mowing frequency to keep the weedy leaves down at the same
height as the surrounding turf leaves and enjoy the white flowers for a couple
of weeks in the early spring.