Jeff from Gordonsville, Va writes
You can apply a post-emergent herbicide such as 4-Speed XT in the morning or afternoon in mild weather. Be sure you do not apply in the hottest part of the day if temperatures are over about 85 degrees since that may cause injury to desirable grass in the area. If you need to apply 4-Speed when the afternoon temperaturs will be hotter, then it would be best to apply the herbicide in the morning when desirable plants are less susceptible to damage. Be sure to read and follow the complete product label.
Answer last updated on: 04/27/2021