You can use either artificial or natural light. Natural light can be hard to control, especially when you are not around. LED light strips, in the range of 6,000-7,000 K, are an easy way of providing artificial light into the growing space without the drying effects of natural light. You can switch them on and off whenever you want, even going so far as to use a remote switch when you aren’t around. Just make sure that your strips are waterproof!