If you will be reseeding the area, turf species listed on the product label can be seeded one week after the application of the Q4 Plus Turf Herbicide.
According to the product label, you should not mow 2 days before or 2 days after applying Q4 Plus Turf Herbicide.
Q4 Plus Turf Herbicide should only be mixed when you are ready to apply the finished solution. You will want to use within 24 hours for the most effectiveness.
The health of the plant will depend on how long it takes Q4 Plus Turf Herbicide to kill weeds/crabgrass. The weeds normally will start to die within one week of application but could take up to three weeks. A second application may be needed.
Most insecticides containing the active ingredient Quinclorac, such as Q4 Plus Herbicide, will have similar labeling to allow the clippings from the first 3 mowings after application to remain on the turf. Since quinclorac stays active for many weeks and needs as much contact time on the target plants as possible, this helps to get the most effect from your sprays. Basically, we do not want to cut the grass and remove the product that we've just applied before it has had time to kill the target weeds.
Another reason to allow clippings to remain is so that they are not mulched too quickly, potentially causing damage to desirable plants while the quinclorac may still be active enough to damage susceptible plants.
Per the product label for Q4 Plus Turf Herbicide it states the following:
Certain spray tank additives such as surfactants may reduce the selectivity on the turfgrass. Use adjuvants only when your experience indicates that the tank mixture will not result in objectionable turf injury.
Q4 Plus Turf Herbicide does not require the use of a surfactant. You could certainly use a marking agent with it.
Q4 Plus Turf Herbicide can be applied with a hose end sprayer but only if can be calibrated to the rate needed per 1000 sqft. Keep in mind that an application through a hose end sprayer may not be as accurate as using a hand pump sprayer. We have a video here that explains how to calibrate your sprayer for the amount of water it takes you to cover 1000 sqft