I have no idea if that would still be any good or not, Deb.
Not familiar with it, I just know that the tomato plants in particular, are considered "heavy feeders" if you had something.
There might be a date code on that container. I dont know if, after the date, it is just less effective /less potent but still fine, or if it could do any harm. Not familiar with the stuff they put into that formula.