Black medic is an annual weed that can sprout and spread into unwanted areas unless efforts are made to keep it under control. Also called hop medic, black clover, or trefoil, black medic can take over lawns, gardens, fields and pastures, and more.
Learn more about when and where Black Medic grows below so you can prevent and control this broadleaf weed.
When Am I Likely to Find Black Medic?
Black Medic is typically a summer annual weed that grows from seed that germinates in the spring. In more temperate climates, seeds may germinate in the fall, or it may grow as perennial.
Black Medic plants flower in the spring and summer from April to July. The flowers are then replaced with pods that contain the seed.
Knowing when this weed seed germinates is key to preventing black medic with pre-emergent herbicides.
Where Does Black Medic Grow Best?
Black Medic can grow in a wide variety of conditions.
It is most commonly found in pastures and fields, in gardens, in waste areas, and along riverbanks and railroads. The small yellow flowers of Black Medic can be seen alongside many roads and paths across the contiguous U.S. and southern Canada.
Black Medic favors dry, sunny areas of disturbed soil that are left untended. It can grow in compacted areas and is often seen along sidewalks and curbs.
Because it can turn atmospheric nitrogen into nitrogen the plant can utilize, Black Medic plants can grow in areas of low-nitrogen. Seeing Black Medic, and other clovers, growing in your lawn can often be a sign of nitrogen deficiency in the soil. Improving lawn conditions, including nutritional needs and compaction, can help stop Black Medic from taking over.