C# Jumping Issue

I've created a basic script for a 3rd person character controller and it works perfectly except for one issue with jumping. No matter what I set the jumpSpeed variable to, the character jumps only about .2 in the y axis.

Here's the code:

using UnityEngine; using System.Collections;

public class SpartanController : MonoBehaviour {

 public int horizontalSpeed = 1;
 public int verticalSpeed = 1;
 
 public int rotationSpeed = 20;
 
 public int jumpSpeed = 100;
 public float gravity = 14.0F;
 
 private Vector3 moveDirection = Vector3.forward;
 private CharacterController controller;
 
 void Update()
 {
     controller = gameObject.GetComponent<CharacterController>();
     
     if (controller.isGrounded)
     {
         // fully control character
         float horizontalDirection = Input.GetAxis("Horizontal") * horizontalSpeed;
         float forwardDirection = Input.GetAxis("Vertical") * verticalSpeed;
         moveDirection = new Vector3(horizontalDirection, 0, forwardDirection);
         
         // get jump event
         if (Input.GetButton("Jump"))
         {
             moveDirection.y = jumpSpeed;
         }
     }
     else
     {
         // less control over character, gravity applied
         float horizontalDirection = Input.GetAxis("Horizontal") * horizontalSpeed / 2;
         float forwardDirection = Input.GetAxis("Vertical") * verticalSpeed / 2;
         moveDirection = new Vector3(horizontalDirection, moveDirection.y, forwardDirection);
     
         moveDirection.y -= gravity * Time.deltaTime;
     }
     moveDirection *= Time.deltaTime;
     
     if (moveDirection.magnitude > 0.05)
     {
         transform.LookAt(transform.position + new Vector3(moveDirection.x, 0, moveDirection.z));
     }
     
     controller.Move(moveDirection);
 }

}