Johnsongrass and crabgrass are invasive weeds that can overtake your lawn. Crabgrass is a low-growing grass most often seen in lawns, flower beds, and vegetable gardens. While you may find Johnsongrass growing in your lawn, it will also grow in pastures, crop fields, and the edge of the road. Johnsongrass is much coarser than crabgrass. If left alone, Johnsongrass can grow up to 8 feet tall. 

Mowing is one of the most important ways to maintain your lawn because it encourages grass to grow horizontally, creating a fuller, more uniform yard. On top of mowing your lawn, you’ll want to routinely fertilize your lawn, water it regularly, and take care of pests the moment they arise. 

Jet washing can wash away weeds without bending or kneeling to pull them. However, the results will likely be fleeting because the weeds will return unless you use a stronger method that takes them out at the root. Use a jet washer for short-term weed removal, but use a stronger method if you want to get rid of weeds for good.

Typically seasonally, but tailored schedules depend on local conditions and plant types.