Like have been said, there is no need for trim when you are landing any model, also take note that there is a difference between trimming and a landing condition which is a preprogrammed situation on the radio which deploy flaps and give some effect on elevator for a hot plane (or WWII, or other scale plane) to land.
The use of new computerized radios which have many features, give you the easiness of a landing condition to ensure a safer landing assuming that the plane needs flaps to guarantee enough low speed vs. stalling.
Those features may be set in almost all type of plane that uses separate servos for ailerons and are controlled by separate channels.
In a regular basis, talking about trainers and sport planes there is no need for trim when you are approaching to land, but also take note that when your plane is descending then your throttle stick becomes the elevator and the elevator stick becomes the speed control.