You'll have to tell us what kind of herbicide it is. What's the name of it?

the name of it is TotalKill by ortho. the first ingredient is Prometon

I suggest that you call the hot line number on the label of this product. I suspect that this site has been contaminated for quite some time, as it is used as a pre-emergent as well as a contact killer. These herbicides are made to adhere to soil particles so that they can stay in place within the root zone of any plant that comes near it.

I just called the number and was told it would be 2yrs before I could plant anything. This stinks!! I'm new to gardening. I just needed something to kill the grass as well as the weeds.
live and learn i guess.

Thanks for letting us know. Now, I'm not scolding you but here's the general rule about reading labels: Read carefully before purchasing the product; read again before mixing, read again before applying, and read again before storing. :-) I'm not kidding.