I'm more convinced now that your only problem is not enough light, Arico. Those plants look pretty healthy to me, other than being a little bit "leggy". This would be from too little light earlier in their lives. Winter sunlight is pretty weak, so even if you had them in a bright sunny window, they might not get enough to grow sturdy stems and dark green leaves.
I'd assume you plan to lift the bulbs in the fall when the foliage dies back, then store them indoors through the winter? Next year, I'd wait until at least February to start up the bulbs, and give them as much light as you can once they start to grow. If you can set up a supplemental light system for them, you could start them earlier.
