Grow Lights

Grow lights replace the sun indoors, and getting them right matters more than almost any other equipment choice. This page covers light types, intensity, hanging height, and schedules.

Light types compared

Modern LED fixtures dominate home growing for efficiency and adjustable output. Older HID lights still work but run hotter and use more power for the same light. Whatever type you choose, even coverage across the whole canopy matters more than a single bright hotspot.

How much light, and how high

Seedlings need gentle light, vegetative plants need strong steady light, and flowering plants need the most. Hang fixtures at the height the maker recommends for your stage, then watch the plants: stretching means too little light, while bleached or curled top leaves can mean too much.

Light schedules

Vegetative growth typically runs on long days, while flowering is triggered by longer nights for photoperiod plants. Keep the schedule consistent, since light leaks and irregular hours stress plants and confuse flowering. Automatic varieties follow their own age-based schedule instead.

Related: Grow Room Design, VPD and Environment, Cultivation Supplies