I was at my favorite garden center recently and noticed a half price sale on a kit to grow herbs in the window. I was a little reluctant to buy it because the only window available to me with sun is only partially facing south. When I combine that with winter in New Hampshire and the short daylight, I was less than convinced that I could grow herbs successfully. But, I am always up for a challenge and did spend the $7.50, (half price). But, before I stuck them in the window, I thought about ways to increase my odds of harvesting some Thyme, Parsley, and Basil.
My main concern is that the window gets pretty cold at night and that translates to poor germination and growth temperatures. So I decided to build sort of an insulated box with a couple of 7 1/2 watt nightlight bulbs. I build a lot with Styrofoam insulation board. This type of foam board is typically 1 inch thick and goes together well with 3 inch drywall screws. (Also called sheet rock screws). That way, I can make a temporary project and reuse the board after the experiment is over. The two photos below show the layout: