How to get rid of weeds growing through rocks in the landscape?

Pull then out then spray weed killer in the place they were

Boiling water or epsom salt followed by boiling water or vinegar. I do all of them. Vinegar will kill anything it comes in contact with, so be careful around plants you wish to keep.

If by safest, you mean least likely to harm pets or wildlife, use boiling water. I get an electric tea pot with the extension cord, fill it from the hose, and douse the weeds I want to kill when the water starts to boil. It takes a while, but leaves no residue. After the plants wilt, go back and collect them so that any seed pods don't get replanted.

Spray weed killer, wait until they will and than pull out. Deleted vinegar sprayed into the soil to get to any remaining roots.

I use one cup of bleach, one cup of salt to two gallons of water in a garden sprayer. Spray them down till saturated. The object is to get down to the roots. Especially dandelions. Their roots can be up to three feet long.

http://www.hometalk.com/diy/outdoor/pest-repeller/four-killer-ideas-to-get-of-weeds-forever-29632816

Boiling salt water works. Just pour it on. I killed off an Oregon grape doing that. I used rock salt.

Charcoal lighter fluid/ gas/ or paint thinner and a match.

I know gas will do it but I'm scared.

Here's a post that might help - https://chascrazycreations.com/home-made-weed-killers/

I use a good-sized spray bottle that's easy to hold and mix 1 gallon of white household vinegar with 1 cup of table salt and 1/4 cup of Dawn dish-washing soap. Mix well in a large jug; label it and then poor the solution into the spray bottle. Shake well and then spray onto the plants you want to get rid of. Within a day or two they will turn brown and die another few days. Sometimes I pull the weeds, etc. out and then spray the area where they were well. Just don't spray on plants you want to thrive nor spray just before rain. You want a few days of sunny weather after you've sprayed. I keep this recipe on hand so whenever I notice a weed I can immediately spray it.

Hi Shelley: Here's the recipe I use: mix 1 cup of table salt with 1 gallon of vinegar. add 1 tablespoon of plain dish soap. Apply to the leaves of the weeds, not to the soil. Here's a great site that talks about this and how to do it: Does Vinegar Kill Weeds? How to Use Vinegar in Your Garden - Bob Vila