You can click on any task and drag it to move that crop planting schedule to a different time of year.
Here is an example of moving a lettuce planting schedule one week later in the yearly view:
Dragging it one week later. The rest of the tasks for the planting schedule move to match:
Here is an example of moving a crop planting schedule in the timeline view:
Click and dragging the lettuce planting schedule to the fall:
Enjoy the flexibility of moving any of your planting schedules to the exact time that works best for you!