If you are suffering with leaving your pitch shots to the green short of the flag, there will normally be two main causes for this fault.
The first fault would be not taking a big enough backswing and generating too little club head speed and the second fault could be decelerating into the impact area and having too short a follow-through.
If you feel you are guilty of either of these mistakes, try to work an early wrist break into your backswing for all chip and pitch shots. Breaking the wrist early in the backswing will not only lengthen your whole swing and lead to a more accelerating downswing, but it should also encourage a steep angle of attack and therefore a better contact on the ball.
Having a wide one-piece takeaway is a very positive action to feel with longer clubs and mid irons. However, with your shorter irons and pitch shots, an early wrist hinge, steeper backswing and acceleration through the ball is sure to encourage a better contact, more aggressive movement through the impact area and better judgement of distance and spin.