What Kind of Lights Do You Need to Grow Cannabis?

Cannabis grow lights are an important part of growing healthy plants. But with so many different types and styles of grow lights on the market, it can be tricky to know which one is right for your needs. In this blog post, we’ll break down the different types of grow lights and help you choose the best option for your cannabis grow operation.

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Indoor vs. Outdoor Lights

cannabis plants need light to grow, but not all light is equal. The right kind and amount of light is essential to getting strong, healthy plants that produce lots of buds. Whether you’re growing cannabis indoors or outdoors, you’ll need to make sure your plants are getting the right kind of light for their stage of growth.

Indoor lights
For indoor growers, the most common type of lighting is artificial lighting from grow lights. Grow lights come in a variety of shapes, sizes, and spectrum types, so it’s important to choose the right one for your grow space and stage of growth.
-HPS (high pressure sodium) lights are a popular choice for cannabis growers because they produce a lot of light in the red and yellow spectrum, which is ideal for flowering plants.
-MH (metal halide) lights are another type of HID (high intensity discharge) light that produces a slightly different spectrum than HPS lights. MH lights are often used during the vegetative stage of growth because they promote strong leaf and stem development.
-LED (light emitting diode) grow lights are a newer technology that is becoming increasingly popular with cannabis growers. LED lights use much less electricity than HID lights and don’t produce as much heat, making them ideal for small grow spaces. LED lights are available in a variety of spectrums, so you can choose one that’s tailored to your plants’ needs.

Outdoor Lights
For outdoor growers, the best type of light is natural sunlight. cannabis plants need at least six hours of direct sunlight per day to thrive, but more is better. If your plants are not getting enough sun, you can supplement with artificial grow lights to make sure they’re getting enough light.

Different Types of Lights

Different types of lights are required depending on the stage of growth of the cannabis plant.

During the vegetative stage, when the plant is growing leaves and stems, a grower will usually use a metal halide (MH) or high-pressure sodium (HPS) light. MH lights emit a blue spectrum of light, which promotes leaf growth, while HPS lights emit an orange/red spectrum of light, which promotes stem growth.

During the flowering stage, when the plant is growing buds, a grower will usually use an HPS light. The orange/red spectrum of light emitted by HPS lights promotes bud growth.

CFLs (compact fluorescent lamps) can be used during either the vegetative or flowering stage. CFLs emit a full spectrum of light, which is beneficial for both leaf and bud growth.

The Importance of Light Spectrum

Not all light is created equal, especially when it comes to growing cannabis. The right light spectrum can mean the difference between productive plants and stunted growth. In general, there are two types of lighting that can be used to grow cannabis natural sunlight and artificial light.

Natural sunlight is obviously the preferred method, but it’s not always possible (or practical) to grow cannabis outdoors. That’s where artificial light comes in. Artificial lights come in a variety of types, each with its own advantages and disadvantages. The most common types of artificial lights used to grow cannabis are fluorescent lights, high-pressure sodium (HPS) lights, and metal halide (MH) lights.

Fluorescent lights are often used as a “starter” light because they are relatively inexpensive and easy to set up. However, they are not very efficient and don’t produce as much light as HPS or MH lights. HPS lights are more expensive than fluorescent lights, but they are more efficient and produce more light. MH lights are also more expensive than fluorescent lights, but they produce a different kind of light that is better for certain stages of plant growth.

No matter what type of light you use, it’s important to make sure that your plants have access to the right kind of light spectrum. The best way to do this is to use a combination of different types of lights. For example, you could use HPS lights for the vegetative stage and MH lights for the flowering stage. You could also use a combination of HPS and MH lights for both stages. The key is to experiment and find what works best for your plants.

The Right Amount of Light

Cannabis, like all plants, needs light to grow. But not just any light will do. The right kind and amount of light is critical to a plant’s development, so it’s important to understand the basics of cannabis lighting before you start growing.

Cannabis plants need two types of light: direct sunlight and indirect sunlight. Direct sunlight provides the energy that plants need to create their own food through photosynthesis. Indirect sunlight helps plants grow strong stems and leaves.

Ideally, your cannabis plants should have a minimum of six hours of direct sunlight per day. If you live in an area with limited sunlight, you can supplement your plants’ natural light with artificial lighting.

There are a few different types of artificial lights that can be used to grow cannabis: fluorescent lights, incandescent lights, and LED lights. Each type of light has its own unique benefits and drawbacks.

Fluorescent lights are inexpensive and emit very little heat, making them ideal for small spaces or for seedlings and clones that are sensitive to heat. However, fluorescent lights are not as bright as other types of artificial lights, so they may not be suitable for large or mature plants.

Incandescent lights are brighter than fluorescent lights but generate more heat. This makes them better suited for larger spaces or for plants that are tolerant of heat. However, incandescent lights use more electricity than other types of artificial lights and can be a fire hazard if not used properly.

LED lights are the most energy-efficient type of artificial light, but they can be expensive upfront. LED lights also emit very little heat, making them a good option for small spaces or for seedlings and clones that are sensitive to heat.

Lights and Heat

Cannabis plants need light to grow – but not just any light will do. The type of light you use, and how much heat it gives off, will determine how well your plants grow.

There are three main types of light that can be used to grow cannabis: incandescent (standard household bulbs), fluorescent (compact fluorescent bulbs or tubes), and high-intensity discharge (HID) lights. All of these lights give off some heat, but HID lights give off the most.

Incandescent lights are the cheapest to buy, but they are also the least efficient and give off the most heat. Fluorescent lights are more expensive, but they use less energy and give off less heat. HID lights are the most expensive, but they are also the most efficient and give off the least amount of heat.

The best way to determine how much light your plants need is to ask a professional at your local grow shop. They will be able to help you find the right lights for your specific situation.


In order to ensure that your cannabis plants get the ventilation they need, you should purchase a fan that is specifically designed for grow tents. These fans will help to circulate the air and bring fresh air into the tent, which is essential for keeping your plants healthy. In addition to a fan, you will also need to purchase an exhaust system that will help to remove the hot air from the tent.

Cannabis Light Schedules

Cannabis Light Schedules
Just like every plant, cannabis needs light to grow. The amount of light and the duration of light exposure that your plants need will change as they progress through their life cycle. Here is a general guide to how much light your cannabis plants need at different stages of growth.

Seedlings and young plants: 12-18 hours of light per day
For the first few weeks of life, your cannabis seedlings will do best with 12-18 hours of light per day. You can provide this using either natural sunlight or artificial grow lights. If you are using artificial lights, choose a cool white fluorescent light (CFL) or led grow light. Keep your lights about 6 inches away from the top of the plants to prevent them from getting too much heat.

Vegetative stage: 18-24 hours of light per day
Once your plants have reached the vegetative stage, they will need 18-24 hours of light per day to continue growing quickly and vigorously. You can provide this with artificial lights or by training your plants to grow sideways using a technique called “screen of green” (SCROG). This allows them to receive more even illumination from natural sunlight.

Flowering stage: 12 hours of light per day
When your plants enter the flowering stage, they will begin to produce buds. To Flowering

Different Grow Stages

As your plants progress from clones or seedlings to fully mature adults, they will go through several stages of growth. Each one requires different care, including the type and amount of light you provide.

Seedlings and clones need 18-24 hours of light per day in order to grow properly. For this stage of growth, you will need to use artificial lights such as fluorescent bulbs or LED panels.

As your plants enter the vegetative stage, they will need 12-18 hours of light per day. During this time, you can switch to using high-intensity discharge (HID) lights such as metal halide (MH) or high-pressure sodium (HPS).

Once your plants start flowering, they will only need 12 hours of light per day. This is when you will want to switch to using HPS lights, as they provide more intense light that promotes better bud development.

During all stages of growth, it is important to provide your plants with the right amount of light. Too much light can lead to leaf burning, while too little light will result in stunted growth.

Clones vs. Seeds

There are two ways to grow cannabis: with clones or with seeds. Clones are cuttings from a mother plant that are then grown into new plants. Seeds are the traditional way to grow plants, and they can be either bought from a seed bank or harvested from a mature plant.

Clones have several advantages over seeds. They are cheaper and easier to acquire, and they grow faster and more predictably than seed-grown plants. However, clones can only be used to grow female plants, so if you want to grow both male and female plants, you will need to use seeds.

When growing with clones, you will need to provide your plants with grow lights that emit both blue and red light. Blue light is necessary for vegetative growth, while red light is necessary for flowering. If you are only growing with seeds, you will only need lights that emit blue light, as all cannabis plants start out in the vegetative stage.


Cannabis plants need light to grow, but the type of light you use is important. Different lights provide different benefits, and some are better for growing cannabis than others.

Here are some common types of lights used to grow cannabis:

LED lights are becoming increasingly popular for growing cannabis. They are more energy-efficient than other types of lights and can be tailored to provide the specific wavelengths of light that plants need.

Fluorescent lights are a good option for small spaces or for starting seedlings and young plants. They are not as energy-efficient as LED lights, but they are less expensive up-front.

High-pressure sodium (HPS) lights are commonly used in commercial cannabis grows. They produce a lot of heat, so they need to be used with ventilation and cooling systems. HPS lights are very energy-intensive.

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