Q.tomatoes and brush killers
How long will the poison be in the soil?

Certified GKH Gardening Expert
Almost all weed killers have a period of time after which where it is safe eat food grown in them. The time varies. Generally, after about a year without the use of any chemical control, it should be ok. As a precaution though, I would suggest washing the fruit thoroughly prior to eating it. Here is more info: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/how-long-does-weed-killer-last-in-the-soil.htm