I installed the fluorescent lighting in my basement all wires seem to be hooked up OK. When we turn it on it is fine for about 2 minutes then the flickering begins to happen. The ground wire seems to be grounded but I could be wrong. Any suggestions?

How many fixtures do you have? If it is just one, try wiggling the bulbs around a little. If that doesn't do it, check the connections including the internals to the fixture. If it is more than one fixture, likely they are not all bad.

You can check the ground by measuring continuity to the white, or the same voltage between the black and the ground and white.

Try a new bulb