How to Identify Common Cool-Season Weeds

Bittercress makes an early spring appearance, often sprouting before all danger of frost has passed. It’s also known as shotweed due to exploding seed capsules, which fling seeds far and wide. Mild winters and wet springs provide ideal growing conditions. Hand-pull if just a few; apply pre-emergent herbicide in fall to foil seed sprouting. Otherwise, keep bittercress mowed to prevent seeds from forming and shooting all over the yard.

Pretty purple flowers decorate on this annual weed in early spring, providing early-season nectar for pollinators. Square stems reveal this weed belongs to the mint family. Plants reproduce by seed, but can also root from stem pieces. Hand-pull when soil is moist.

Invasive and unwelcome, garlic mustard is overtaking native plant species in moist, shady settings. Plants are biennials. The first year, a leafy tuft of triangular, toothy-edged leaves appears. In the second year, white flowers on tall stalks emerge. Focus energy on pulling plants with flower stalks before they set seed. Attack leafy tufts later in the season.

This familiar face is the bane of lawns coast to coast. Toothed leaves form a ground-hugging rosette. Bright yellow flowers fade to puffball seedheads. Dandelion is a perennial weed. Dig or spot-spray if you only have a few offenders. Apply pre-emergent herbicide to lawns in fall to interrupt seed germination.