If you plant crops or sugar cane in your spawn chunks, and you go too far away for them to be visually loaded (they should still be loaded, but you shouldn't be able to see them), they won't grow.

they don't grow in either singleplayer or multiplayer. however, the spawn chunks ARE loaded, as you can see on the timer to the right and on the tab list. the command blocks for that are in the spawn chunks as well. I haven't shown the crops not growing, but i have tested it, and they don't grow.

https://youtu.be/hA64aHbjtC8