Persistance and patience. Gravel has to be kept up on the regular. It traps dirt and seeds, and always will. A pre-emergent can help a lot, but if they are already growing with a vengence it may be too late for this year. You can use weed killers if you want, different folks use different kinds- some prefer organic, some prefer synthetic. Upkeep during the warm season like using a blower to blow off debris/seeds can also help. Depending the the gravel and space, some folks hand tend it and use rakes and pulling to keep it neat.

Dont want to fool with those torch burners. I am looking for athe most effective chemical spray that will kill them. Beesneeds is right - gravel areas are going to have to be tended to regularly just like the flowerbeds. I had thought - put down lots of gravel and it will continue to look like that. I now have learned otherwise. I should know - nothing is maintenance free! So......... interested in learning the best chemical spray to use on the gravel and once I get the area weed free, will be prepared to watch for emerging weeds and respray to keep it looking nice.

I found Preen to be highly effective on a gravel path.