Hungry cities

I have a problem with my cities getting too big and requiring either annoying food shipments from other cities. My stepbrother recommends using engineers from other cities to change plains and hills to grasslands. Is there any other way?

Hi!
That sounds a little confusing: How do your cities grow to a point where they need food shipments? Usually, they grow until they are out of food surplus, and then have maybe 1 deficite, which rarely turns out to be a problem.

I came up with a solution (with a little help from my bf). I put an engineer on prairie diamonds and "O" them to grassland. I have only had to do this twice a couple of times. One conversion settles them down.