Kv from Nj writes
The general rule for spring is to apply your pre-emergent herbicide treatment such as Howard Johnsons Dimension 0.27G Herbicide after the ground has thawed from the winter but before the temperature of your soil reaches 55 degrees, as that is when crabgrass begins to germinate. Other weeds will germinate when the soil temperature is between 55 and 65 degrees. You can use a soil thermometer to determine the temperature of your lawn/area. You will want to measure the temperature of the soil a few inches below ground. The ideal time to apply a fall pre-emergent herbicide to your yard is between August and November when the soil temperature is below 70 degrees and dropping. .
Answer last updated on: 02/03/2023
