How to protect rest of yard from KillzAll?

The guy that cuts my family's lawn offered to get rid of the weeds growing in between ours & the neighbors fences. But I have an active garden growing not too far from where the weed killer will be applied, so is there anything I need or can do to protect MY plants?

Or rather how does it work, and how big of an area does it effect?

There's also a mulberry tree growing in the midst of the weeds, will it die? Will it be harmful to eat the fruit off of the tree? If it doesn't die, how long do I have to wait before the fruit is safe again?