On my home page, the background image in the left content section suited the original template by only going half way down the columb.
Now i need to stretch the bg image down the full left content columb. i have tried changing my css without success.

You mean stretch or tile? If the latter just remove repeat-x.

Do you want the image to both stretch and repeat itself?

You might use the "background-size" property to stretch it, but the result may depend on wether the element's height is known or not.