How not to show text when colecting all items?

I have 5 items in my level and when I collected one text show up on the screen. I would like for the text to appear when I collect the first 4 items of my level and no text when I collect the last one. How can I do this? Here is my code I have on my items.

using UnityEngine;
using System.Collections;

public class Item : MonoBehaviour
{

//Variables for text output on screen and audio
public GUIText TextOutput;
public AudioClip SoundToPlay;

//Variables for the item pieces
public static int itemCounter = 0;



//Code for when the player collides with an item to collect.
void OnTriggerEnter (Collider other)
{
	//When the Player enters the area
	if (other.tag == "Player")
	{
		//The audio will play
		AudioSource.PlayClipAtPoint (SoundToPlay, this.transform.position);
		
		//Text will appear on screen
		TextOutput.text = "Look around the town for more pieces!";
		
		//Will increase the item count by one
		itemCounter += 1;
		
		//Simulate collection by destroying the item
		Destroy (gameObject.transform.parent.gameObject);

	}

	
}

}

if (itemCounter < 4) TextOutput.text = "Look around…