How to Grow Cannabis Indoors

Here’s a look at the basics for growing cannabis indoors at home, including lighting needs, adding nutrients, when to water, and more.

Growing cannabis indoors can seem like a daunting task, but with the right set of equipment and tools, even gardening beginners can succeed at producing a high-quality yield from their marijuana plants come harvest time.

While cannabis will grow outdoors, doing so makes the plants more susceptible to problems related to fluctuations in environment and exposure to pests. On the other hand, growing marijuana indoors gives you greater control over the growing environment, ensuring that your marijuana plants receive the ideal elements they need to flourish.

When growing cannabis indoors, you will need to control these conditions:

  • Nutrients
  • Water
  • Light
  • Temperature
  • Humidity

To help simplify the indoor cannabis growing process, here is a clear, easy-to-digest cannabis grow guide, which provides an overview of the tools a first-time marijuana grower needs to get started.

how to grow cannabis

Grow Area Needs

When growing cannabis indoors, you’ll need to decide where in your home that you will want to set up your grow area. A personal grow area doesn’t need to be big: a space about two feet deep, three feet wide, and four feet tall should be adequate for beginners looking to grow a couple of plants. Growers have been known to use cabinets or closets in their homes because a proper growing space needs to be shielded from external light.

Here’s what else you’ll need:

Marijuana Grow Tent

If you’d rather not use a cabinet or closet, you can purchase a grow tent and use it to create an enclosed, controllable space within a larger room.

Grow tents are your all-in-one indoor canopy. They have reflective inner walls and are designed to accommodate exhaust fans and light kits, and they’ll save you from having to staple or drill into your walls. Some growers opt to build their own type of “grow tent” out of lumber. 

Some grow tents and grow cabinet’s come complete with lighting, fans, watering systems. Some marijuana grow kits even come with a camera and smartphone compatibility to make it easy to monitor and adjust your plant’s growing environment.

Buckets or Burlap Sacks

Quality buckets and burlap sacks work really well for growing cannabis. If using buckets, simply drill a few holes in the bottom for drainage, making sure any tray you place underneath to catch water doesn’t inadvertently seal those holes. Burlap sacks are ideal for growing marijuana because they allow more air to reach the plant’s roots, which can encourage healthier cannabis plants and bigger yields.

Organic Soil Mix

Most high-quality organic soils available at gardening and grow shops will provide your marijuana plants with the nutrients they need to be healthy. Avoid soils that indicate they provide extended-release nutrients, which can wreck the balance of the nutrients, particularly during your plants’ late stages of growth.

cannabis soil

Lighting Equipment

Lights for your growing space are essential, as they replace the sun in an indoor garden, so this is a good place to invest in getting quality equipment. Keep in mind that, when growing cannabis indoors, your lighting setup will likely be your biggest expense in setting up your cannabis growing space. There is a wide variety of lighting choices. While it is possible to purchase the equipment you need individually, more and more, complete lighting kits are becoming available, taking much of the work out of purchasing and assembling your cannabis plants’ lighting. 

Light Kit

For beginners and experienced marijuana growers alike, a popular choice is 400w high-intensity discharge (HID) light kits. These lighting kits typically come complete with everything you need to grow indoors, including:

  • Electronic ballast
  • Bulbs
  • A reflector
  • Hangars

All in one lighting kits like this can be costly, but they are easy to set up, produce great yields, provide the fastest grow time. 

cannabis grow lights

Environmental Control and Monitoring Tools

Exhaust or Small Circulation Fan

An exhaust fan pulls fresh air in and pushes warm air out of your growing space. This provides your marijuana plants with much-needed fresh air that circulates to prevent stale air from building up and leading to mold and mildew. Constant fresh air moving through and around your cannabis will also assist in temperature and humidity control and strengthen your cannabis plants’ branches so they can hold up bigger, heavier flowers.

Thermometer/Humidity Gauge

A thermometer and humidity gauge should be used to regularly monitor the growing environment. Cannabis grows best between 72 and 76 degrees Fahrenheit. Too high of a temperature can kill your marijuana plants, while too low of a temperature can allow powdery mildew to develop.

The right level of humidity is important for cannabis plants, too, but for best results, it should vary depending on the stage of growth:

  1. When your weed is seedlings or clones, the ideal humidity is 65-70 percent.
  2. During vegetation, humidity levels can be lowered, with a range of 40-70 percent.
  3. When your cannabis is flowering, the humidity should be 40-50 percent.

You can lower humidity by increasing fresh air supply with your exhaust fan.

Nutrient Needs

pH Meter or pH strips

A pH meter or pH strips test your soil’s pH, or how acidic or alkaline it is. A pH meter features a probe that is inserted into the soil and then provides you with a pH reading. Disposable pH strips are inserted into water flushed through your soil and turn a specific color depending on the pH.

Both provide you with a pH reading on a scale of 0 to 14, with more acidic soils having a lower pH, more alkaline soils having a higher pH, and a pH of 7 being neutral.

Cannabis thrives in soil that’s neutral to slightly acidic, with a pH of 6.0 to 7.0, as it helps the plants more efficiently absorb the nutrients they need to flourish. If you find that your soil’s pH is outside the ideal range, you can adjust it by using “pH Up” or “pH Down” solutions found at your local gardening shop.

Learn more about cannabis pH and other topics on our Cannabis 101 page.

pH for marijuana


Cannabis plants need to absorb certain nutrients to produce healthy yields, among the most important of which are:

  • Nitrogen
  • Phosphorus
  • Potassium

There are many nutrient product options to choose from, which can cause new growers to quickly become overwhelmed. Don’t despair – cannabis-specific pre-mixed organic soil nutrient solutions are ideal to make sure you get it right.

grow cannabis plants

Can You Grow Cannabis Legally?

As cannabis laws continue to evolve throughout the United States, more and more people are looking into growing their own cannabis at home.

Today, more than half of U.S. states allow people to personally grow cannabis legally. Over 30 states and Washington D.C. have legalized medical marijuana, and 11 states and Washington D.C. have legalized weed for recreational use.

You can learn more about the marijuana laws where you live by visiting our Overview of U.S. Marijuana Law page.

Learn More about Growing Cannabis

You can learn more about how to grow your own cannabis, including the best practices for produce healthy cannabis flowers and curing your cannabis through our Cannabis 101 page.