This is a new invasive weed in the neighborhood that spreads by stolons and forms thick carpets from farms to city gardens up to a foot tall. Like many weeds, creeping buttercup's competitive growth will crowd out other plants. In fact, one plant can spread over a 40 square foot area in a year. Bloom time--the flowers usually have five (sometimes 10) glossy, bright yellow petals growing on singly long grooved stalks--is from March to August and then they produce seeds which can remain viable in the soil for at least 20 years.
Depending on the temperature, creeping buttercup either overwinters as a rosette or dies back to ground level. In either case, the nutrients stored in the short swollen stem produce rapid growth in spring, between March and June.
How hardy is the plant? It is frost tolerant and will survive moderate droughts. It doesn't mind trampling, compacted soils and grazing and mowing will not control it. The most effective broadleaf herbicide to use on buttercup is Milestone, Grazon or Banvel. Pull up any new seedlings before they establish runners.
Healthy grass is the secret to controlling the weed. Overseed lawns and pastures, fertilizing as needed and do not over graze. Adding lime can improve grass health and may be a deterrent to buttercup becoming established.