Regarding dynamic texture

I tried to create a dynamic texture on my project, but it doesnt seems to fit with the size of the ground. but when i tried something similar in plain PG it worked. what can be wrong?

code i used in my project:
var ground = BABYLON.MeshBuilder.CreateGround(“ground”, {width:4600, height:3200});
ground.position.x = 2300;
ground.position.z = 1600;

var textureResolution = 512;
var textureGround = new BABYLON.DynamicTexture(“dynamic texture”, textureResolution, scene);
var textureContext = textureGround.getContext();

var materialGround = new BABYLON.StandardMaterial("Mat", scene);    				
materialGround.diffuseTexture = textureGround;
ground.material = materialGround;

var img = new Image();
img.src = "/textures/floor.jpg";
img.onload = function() {
    //Add image to dynamic texture
    textureContext.drawImage(this, 0, 0);

    //Add text to dynamic texture
    var font = "bold 44px Arial";
    textureGround.drawText("Grass", 75, 135, font, "green", null, true, true);

Solved myself… Dropped the resolution to 256. and it workked