Once your plant has reached a certain age through its lifecycle, it may require more intense light to produce the energy it needs through photosynthesis.
Ballasts are an essential part of your lighting setup as they enable you to properly regulate and limit the power that is being fed to your HID lamp. This ensures that the light being produced by this lamp has a consistent current and offers you stable operation.
Ballasts come in various formats, the most popular being a magnetic ballast. This type of Ballast features a large copper coil that becomes magnetic as power is drawn through the coil. As the coil becomes magnetic, it restricts the amount of power that is reaching the lamp and also regulates the wattage supplied. This is all relative to the size of the lamp.