Yes, except for winter. Any unharvested crop still left at the advent of winter becomes a withered plant.
They aren’t dependent on season. The earliest you can plant is usually sometime around mid-spring, although you can sneak in some noon planting about a week prior if the temperature is high enough.
No. You can fertilize them, cutting down the growth time but also reducing crop yields. Primarily done to expand a seedstock.
Yes. I built a nifty little rig a few games back to do everything for me. Just a couple reapers, followed by plows, followed by the cab, followed by seed drills, with wheels on the outside so as not to run over tilled fields or crops. Worked like gangbusters.
