Is it Hard to Grow Marijuana Indoors?

Growing marijuana indoors might seem like a daunting task for beginners. How many nutrients are enough? What grow lights should I get? What exactly is going on with growing mediums? The abundance of tutorials out there are capable of confusing even experienced growers. However, there is no reason to make marijuana growing harder than it has to be.

In this article, we are going to share with you a simple 5-step guide about how to grow marijuana indoors to make things even easier for you. Remember, this is a foolproof method for a basic marijuana grow and doesn’t cover every aspect extensively. For more information about specific topics, follow the links to our in-depth articles!

This guide can be adapted to any grow style, budget or desire. Anyone with a little bit of spare time and the will to learn can become a marijuana grower and enjoy their quality product at home.

Understanding Marijuana Plants’ Needs

Marijuana plant needs are pretty specific. Like all living things, cannabis needs a few things to thrive.

  • A suitable growing area with sufficient ventilation
  • A lot of bright light
  • A growing medium (they have to grow on something, don’t they?)
  • A steady supply of quality nutrients
  • A great genetic lineage
  • Water (obviously)

It doesn’t take much more than this to produce some of the best marijuana you’ve ever smoked. So, let’s clear the air and finalize what is essential before you stick your seed into the growing medium of your choice!

A Simple Five-Step Guide to Grow Marijuana Indoors

This guide highlights the most critical parts of setting up an indoor marijuana grow before you germinate, plant and start caring for your seeds. For more information about growing from seed to harvest, check out our website! You’ll find tons of useful information.

Step 1: Choose An Area to Grow Marijuana Indoors

The first step towards greatness is finding a suitable space for your indoor garden. As long as you have easy access to water and air circulation, this can be anywhere, from a closet to a garage.

Measure the dimensions of you grow space taking into account the following:

  • You’ll need sufficient room to maneuver, as you’ll have to water and check your plants frequently.
  • Your plants will eventually grow. Remember, you’ll have to fit them, yourself and your grow lights in your grow space!
  • Your crop requires a constant circulation of air, so you might want to think about installing an exhaust fan.

You also have to make sure that the temperature of your marijuana grow space will be manageable. Even the coolest-running grow lights still emit some heat. Ensure that the temperature never exceeds 30ºC or falls below 20ºC. Marijuana plants in the vegetative stage need more warmth, while older plants will produce more buds at slightly lower temperatures.

To keep the temperature in check:

  • Use a thermometer to measure any sudden fluctuations. They are cheap, and you can usually find some good deals at home improvement and pet stores (some of them even have built-in hygrometers!).
  • Adjust the power of your grow lights and make sure they are not too close to the plant canopy. Unless you have a dimmable unit, you will also need to readjust their position as your plants grow. You will find more about grow lights in the next step!
  • If the temperature in your soon-to-become grow space is already high, consider using a fan or a small air conditioning unit to keep things fresh.

Growing indoors can be incredibly cheap, especially for smaller-time growers. If you don’t have any space available, there are hundreds of affordable indoor growing systems available on the market. In any case, if you are not planning to grow more than 4-6 plants, this is as easy as it gets!

Step 2: Learn All About Indoor Grow Lights

Choosing the best grow lights for your needs will be the most important (and the most costly) investment you will have to make when growing indoors. Indoor growing requires specialized bulbs that are much more powerful than ordinary incandescent lighting.

There’s a lot of types of cannabis grow lights available on the market:

  • Fluorescent Light bulbs (CFLs, T5 / T8)
  • LED grow lights
  • HID grow lights
    • Metal Halide (MH)
    • High-Pressure Sodium (HPS)

Most of these grow lights require dedicated ballasts to run, as they are considerably brighter than house bulbs. Each one is better suited to different growth phases, has different costs and has its pros and cons. Let’s look at all the different types one by one.

Fluorescent Lighting


CFL bulbs are an ideal starting point for absolute beginners, as they are available everywhere, they fit anywhere, run cool and are basically dirt cheap. Their major drawback is that they are not nearly as bright as dedicated grow lights.

Costs: $1-$10


High output T5 lights are considerably more powerful than CFLs, but their shape makes them a bit tricky to install. Their intensity is not so high, and they must be kept really close to the canopy to be effective. Even then, they tend to fall short of other grow lights.

Costs: $3-$8 per lamp.

We recommend that you use fluorescent lighting if:

  • You intend to keep your plants short and well-trained
  • You want to supplement some light in areas that don’t get enough (like below the canopy)
  • You have a minimal grow space.

It is entirely doable to grow cannabis from start to finish using only fluorescent lighting. It will just take a little bit of effort and care to readjust the lights as your plants reach the flowering stage.

LED  (Light Emitting Diode) grow lights

More powerful than CFLs, LED grow lights come in all shapes and sizes, and they are also much more expensive than anything other in the market! In some cases, the costs associated with LEDs are completely justified. However, there are a lot of shady dealers out there, so due diligence is advisable.

Theoretically, LED grow lights combine the best of all worlds: they can be as powerful as you want, they run cool, and they can grow a marijuana plant from seed to harvest. Each unit is quite different from the other, so there is no standard guide when growing with LEDs.

Costs: $25 (for a single bulb) – >$2000 (1000W+ fixtures)

When shopping for LEDs, make sure you are buying from a reputable company:

  • Ask them whether the listed power output is real. Listing the maximum power output that a LED grow light can produce is the oldest marketing trick in the book. However, rarely do grow lights work at 100% of their potential. Nevertheless, some companies wistfully ignore that fact and list that number as the true power output.
  • Check the price per true Watt. Anything more than $3 per Watt is overly expensive.
  • Check whether the grow lights are dimmable.
  • Check the company warranty and make sure you’re getting a good deal.

HID Grow Lights

Metal Halide (MH) & High-Pressure Sodium (HPS)

Before LED grow lights became all the rage in marijuana growing, there were HID lights. Extremely cheap, intensely powerful and profoundly hot, these lights were the staple of indoor growing for many years.

Aside from the extreme heat generation, the other major drawback of HID grow lights is increased electricity costs. Overall you can get amazing results with MH/HPS grow lights, as long as you get exactly what you need. For example, a 250W HPS fixture is ideal for a 60cm x 120cm x 150cm grow space. Using this as a rule of thumb, you can easily adapt these lights to any grow space.

Costs: $70-$120

The Verdict

There is no single best option regarding grow lights. Anyway, the most important part is not the type of light, but your power needs. If you are confident that you can maintain a healthy temperature for your plants, go for more powerful grow lights but don’t overdo it. For example, 120cm x 120cm grow area will thrive under a 400-600W light

Step 3: Choose a Growing Medium

There are many growing mediums in which you can grow cannabis, each with its own pros and cons:

  • Soil – Tried and tested for millennia, soil is humanity’s go-to growing medium when it comes to growing plants. Get some super soil from your local garden store, plant and water regularly!  
  • Soilless Mixes (Hydroponic) – anything that doesn’t involve soil (including coco coir, perlite, and vermiculite), is considered hydroponic. The plants’ roots are submerged in water, and you just add nutrients.
  • Aeroponics – These methods are not recommended for beginners, as in this method, the plant roots are suspended in misted air. Try something more conventional first.

Soil is by far the easiest solution and it is recommended for first-time growers, as it is more forgiving to mistakes. Of course, that doesn’t mean that you will fail if you opt for hydro, but soil will give you a smoother learning curve.

The critical thing to consider is to give enough room for the roots to expand (the more extensive the root system = the larger, the plant). Also, for your first few grows, it is best if you avoid using some automated watering system and water your plants manually at least once a day. That way, you’ll have a better chance of understanding how growing works and train your eye to detect problems.

Step 4: Choosing and Using Nutrients Wisely

Nutrients are necessary for a vigorous and robust growth, but many growers fall into the trap of thinking that more is always better. Nutrient solutions come in bottles, and their goal is not to “feed” the plant, as the plants make their own food through photosynthesis. Rather, they aid the process of photosynthesis and help plants metabolize their food.

The real challenge with nutrients -especially for beginners- is to find the optimal dosage. Plants can get fatally sick by excessive nutrient buildup, so it takes training to avoid ODing them!

How to find the perfect nutrient “sweet spot”:

  • Start with lower nutrient doses than the ones recommended. And when we say low, we mean about 50% lower.
  • Carefully inspect your plants for signs of discoloration or leaf loss. These symptoms may be the sign of nutrient burn.
  • Use organic nutrients if possible. Synthetic nutrient series are more powerful but contain excessive salt levels that can create problems to your plants. Organics are milder, and therefore more forgiving to mistakes.

Nutrients and Growing Mediums

Nutrients are necessary for marijuana growing whether you are growing hydro or soil. There are specialized solutions for each choice.

Nutrients for soil growing

You can skip this part if you plan on purchasing composted super soil for your first grow. Otherwise, you will need soil nutrients, especially during the flowering stage of your marijuana plants, where energy levels surge, and they tend to use more energy.

Nutrients for hydroponic growing

Nutrients are a necessary part of hydroponic growing, as your plants have no other way of obtaining necessary nutrients. There are solutions that are targeted to your specific growing material (perlite, coco coir etc.)

To recap:

  • If you are just starting out, use half of the recommended dosage on your plants
  • Try to go for organic nutrient solutions to avoid salt
  • If your area has hard or contaminated water, consider using purified water for your plants.

Step 5: Choose A Suitable Marijuana Strain

Let’s start by clearing the air: no matter where you live in the world, marijuana seeds are NOT illegal. So is ordering them from abroad, so you will have no problems obtaining them from any vendor you like. No one has gone to jail for ordering seeds!

Choosing a great marijuana strain is the most important choice you will make regarding your grow. If you are lucky enough to live in places where weed is legal, then you might have an easier time locating breeders that sell quality seeds or clones with great genetics. is an excellent tool for locating high-quality dispensaries that offer seeds of true genetic lines. The rest is up to your personal preferences: There are thousands of strains to choose from for recreational and medicinal purposes. If you are looking for a happy-go-lucky type of high, go for high THC strains. On the other hand, if you suffer from insomnia or anxiety, CBD-rich varieties might be more up your alley.