A Beginner's Guide to Grow Light Setup

big marijuana grow lights
Grow Lights

When you're new to an industry, everything seems a little bit daunting. It's even more intimidating if there are strict legal requirements surrounding your new business, as there are with the marijuana industry. One aspect of the cannabis industry that is particularly challenging is grow light setup for your indoor grow operation. While this subject is extensive, here are some beginners tips to get you started off on the right foot. Here are some recommendations from Home Grown Cannabis Company.


Table of Contents

Basic Light Setup

Before getting too involved in setting up grow lights, it's important to understand how marijuana plants grow best. They like intense overhead light that gives them adequate food and promotes quick growth and abundant bud production. However, if you only use overhead lighting, your plants will probably be tall and thin, which means you won't get much production from the lower parts of your plants.

To combat this, you want to have a secondary light source located about a third of the way down from the ceiling of your grow tent. This light will be aimed toward the sides of the plants, giving the lower sections enough light to grow thick and full of buds. Both the overhead light and the supplemental light should emit blue light to encourage leaf growth, bud quality, and a sturdier plant overall. The overhead light should be a full-spectrum LED or High Pressure Sodium light, while the side light should have a lower light output.

Courtesy: Shutterstock

Lighting for Smaller Grow Spaces

Many beginning marijuana growers start in small spaces, whether it's because they are restricted by law to a limited number of plants or because they are only growing it for themselves. A closet is a popular grow spot, as are smaller spare rooms. However, in these confined spaces, the heat generated from your lights can be a major problem. Additionally, the goal in tight areas like a closet is to grow short, bushy plants rather than tall, skinny ones. This maximizes your bud yield without needing a large number of plants.

To achieve the shorter, bushy plants, use a full-spectrum LED panel that puts out between 300 and 600 watts. Your supplemental side lights should be blue-spectrum fluorescent bulbs or LED bars that have a color temperature of between 5500K and 6500K and an output of 45 watts. LED is a better option for closet setups because they don't generate heat. Fluorescent bulbs do generate heat, but if you only use them for your 45-watt supplemental light, the temperature will be manageable.

marijuana grow lights
Courtesy: Shutterstock

Switch From Blue to Red Light in the Final Stages

For the best results, use blue light for the majority of the growing time before switching to HPS (red light) during the final growth stages. You'll know when to swap out your lights when your plants stop growing vertically and are just beginning their peak bud stage. Red light is ideal for bud and flower production and decreases the time to maturity. In other words, you'll be able to enjoy a higher-quality product more quickly.


It's not difficult to set up an indoor grow area, even if you don't have a lot of space. Using an intense overhead light (blue first, then red) combined with adequate low-level blue side light will give your plants the best opportunity to flourish.