Heating cables are a resourceful way to sprout stubborn seedlings. Many plants hatch better in warm soil, but a space heater doesn't heat the soil to the indicated temperature right away. The right cables depend upon how much soil area you need to heat. Measure the area of the bottom part of the soil--multiply the length times the width. For areas of 1.5 square feet, a small six-foot cable should do fine--for three square feet, use a 12-foot cable. Anything over six square feet requires a cable at least 24 feet in length. For anything greater than this, you'll probably want more than one cable, or try laying down several large heating mats.

For plants that get all of their light exclusively from indoor grow lights, metal halide is definitely recommended. Metal halide light also keeps plants at a compact density, which is great when you're trying to grow in a small space.

Cold-weather growers should pay special attention to their exhaust fans. Heat can be easily lost through the vents, which can hit your wallet hard and make it difficult to regulate temperature. Those in need of exhaust fans for cold-weather greenhouse kits should look for special louvres made of a heat-resistant metal.

The word, hydroponics, is derived from the Greek word hydro, which means "water" and ponos, which means "labor or water-working". Hydroponics gardening involves growing plants with their roots in other nutrient solutions and without soil.