Probably a good adder to my ash mix.

apply early.

Good results, clean out the soil from the cracks where the weeds come up. The cleaner the blacktop edges at the crack yhe better. Then get caulking tubes of blacktop crack sealer at a hardware dept. Fill the cracks with a caulking gun. This prevents the weeds from growing because you sealed them off from access to soil.

Another method is to use vinegar and hot water. Poor over the weeds in the Spring when they are young and not well established. Apply through the season as needed.

How to Kill Weeds with Vinegar

Check the weather forecast before applying vinegar to the weeds. ...
Apply regular, household vinegar to the weeds using a spray bottle or paint brush. ...
Apply boiling vinegar to stubborn, perennial weeds, or weeds that have become well established. ...
Do not water the area for two days.
Reapply as necessary.