When growing indoors, its essential to match the natural sunlight changes throughout the seasons to initiate the different growth stages of each plant. Different temperatures surrounding a plant and the intensity of the sun are triggers for plants that allow them to release chemicals internally that will start them off into the next stage of their lifecycle.
The size if your indoor garden space, as well as the plants you are planning on growing will determine the type of lighting, and the strength of lighting you should use.

High Intensity Discharge (HID) lights are the most popular choice for most indoor growers, and HID setups usually consist of:
Bulbs – Usually Either Metal Halide (MH) or High Pressure Sodium (HPS)
Ballast – This is used to allow the control a constant and consistent stream of electricity through the bulbs.
Lighting Hood or Lighting Reflector – This is used to spread the hydroponic grow lights and the heat being emitted from the bulbs evenly around your grow room so that there are no “heat spots” and so that the light can be distributed further – reducing the need for multiple bulbs.
LED Lighting is a type of lighting system that is relatively new for indoor growing. The initial expense of LED lighting is high in comparison to other types of marijuana grow lights. However, they are highly energy efficient and the bulbs can last for years (in comparison to MH & HPS which may only last one season).

LED lighting also emits far less heat than traditional bulbs which means they are good for very small growing spaces where the bulbs have to be very close to the plants.

Just like traditional bulbs – diy led grow light can be bought that emit different spectrums of light which will help to produce optimum efficiency in the different stages of a plant’s lifecycle.
RGB or Multi-colour LED’s can also be bought, and these types of lights can offer any spectrum of light by “mixing” the primary colours. The same LED bulbs can be used at each different stage of the plants lifecycle by using different filters, eliminating the need to switch bulbs during the plant’s growth.