Growing marijuana indoors doesn’t require a massive green thumb or a tremendous volume of knowledge on how to grow pot. While growing weed indoors does present some challenges for someone new to the hobby – and there’s a ton of misinformation out there about how to grow weed indoors – this endeavor doesn’t need to be strenuous.
We’re here with our easy guide to growing cannabis indoors to help you get started.
Table of Contents
- Start by Setting Up Your Grow Room
- Select Your Grow Lights
- Establish Good Temperature, Airflow, and Ventilation
- Design, Set Up, or Purchase Other Necessary Equipment
- Decide on Soil vs. Hydroponics Growing Medium
- Start Your Seeds and Care For Your Seedlings
- Fertilize and Water Your Plants
- Harvest Your Finished Product
Start by Setting Up Your Grow Room
The first step to growing marijuana indoors? You need to set up your grow space. This can take multiple forms, including a grow tent, grow room, or greenhouse, which we’ll detail below. It doesn’t need to be anything fancy or storebought, but of course, if you’re looking for a ready-made, easy-to-implement solution, a premade grow room or grow tent might be your best.
That said, a grow room can easily take the form of a closet, cabinet, tent, basement, spare bedroom, or even an unused corner of your home.
Grow Tents vs Grow Rooms vs Greenhouses
When you’re just getting started with growing cannabis plants indoors, you may wonder what the easiest solution to help accelerate your progress may be. Grow tents are some of the easiest and most common solutions to growing and storing your plants. Grow tents come in multiple sizes and styles to suit any growing needs. You won’t need to drill or mount hooks or vents and you’ll have maximum control over your growing conditions. These often are sold as ready-to-go grow tent kits, too.
A grow space can take the form of a bedroom, closet, garage, or spare room in your home. This is more of a DIY solution, with no need to buy a tent. You can set up a grow space by purchasing some cheap reflective material and fans. These will use the space you already have so you won’t need to spend much money.
Finally, a greenhouse is a good solution if you want to grow outside. You’ll reap all the benefits of outdoor growing, but without the hassle of an unpredictable climate. You may need to add additional light or ventilation, however.
Other Variables to Consider
Wherever you choose to set up your cannabis grow room, it needs to be protected against light. This sounds counterintuitive since marijuana plants need light to grow – but they also need periods of darkness. Make sure you have no light leaks, as light leaks during periods of growth that are supposed to be dark can cause your plants to put on male flowers.
You will need to work with your plants every day. Sometimes, this might just mean checking on them to make sure they are doing okay. However, you may need to check on them several times of day when you are just starting out. If it’s hard to get to your grow room, this is going to be a major hassle.
No matter what kind of space you pick for your cannabis plants, make sure you are growing cannabis in a clean, sanitized location. You’ll want to surround your plants with surfaces that are easy to tidy up – drapes, unfinished wood, and carpeting are all out of the question.
How much room do you want to allocate for your growing space? You can’t decide on the types of strains you want to grow – or how many plants you are going to grow – until you know exactly how much space you have for growing pot indoors. Each plant will need a minimum of one square foot – you may have to do some measuring. Don’t forget that the canopy of your plants may take up some extra space, too.
Consider starting small. This will be less costly to set up, and it’s easier to keep track of just a few plants than multiple different ones. Plus, if you make a mistake you’re less likely to lose lots of money! However, keep in mind that cannabis plants can triple their size in the early flowering stage, so you’ll want to have extra space just in case.
Temperature and Humidity
Your grow room needs to be warm and humid- but if it’s too warm and humid, you are going to have fungal issues. Make sure you choose an area that receives plenty of adequate ventilation.
In most cases, you are going to need to conceal your efforts at growing weed indoors from your neighbors. Make sure you select a location that is nice and secluded.
Select Your Grow Lights
Light is one of the top concerns you need to make when you are trying to figure out how to grow cannabis indoors. Choose the best lighting setup that your budget will allow – here are the most popular types of grow lights used for growing cannabis indoors.
Also known as high-intensity discharge grow lights, these can be a bit more expensive than incandescent or fluorescent lights but put out a ton of light per unit of electricity. They aren’t as expensive as LED grow lights, though. HID lamps can be broken down into metal halide and high-pressure sodium lights. Metal halide units produce blue-white lights that are ideal for the vegetative stage while high-pressure sodium lights produce reddish-orange light, ideal for the flowering stage.
If you choose to use a HID grow light, you may want to start with HPS – these deliver more light. You will need to buy a ballast, too, and make sure you invest in a good one (we recommend digital ballasts) to help you keep track of your heart. You will also need to purchase reflector hoods that are air-cooled to help add ventilation and cool down the temperature in your grow room.
LED technology is nothing new, but it’s only recently been added to the toolbox of equipment used for growing cannabis plants indoors. These grow lights can be relatively expensive, coming in at about 10 times more than an HID lighting system. However, they offer greater longevity and use much less electricity. They also produce minimal heat and there are designs that generate a full spectrum of light so that you only have to buy one unit.
Fluorescent light fixtures are some of the most popular grow lights for novice hobby growers. They are inexpensive, as the reflector, ballast, and bulbs are all included in the same purchase. They also do not require a cooling system as they don’t generate quite as much heat as other alternatives. However, they aren’t as efficient, so you’re going to spend more on electricity bills over time.
The final type of grow lights on our list are induction lights. These are also referred to as electrodeless lamps and are more efficient versions of fluorescent bulbs. However, they can be hard to find in stores and somewhat pricey as a result.
Establish Good Temperature, Airflow, and Ventilation
Without plenty of fresh air, you are going to have issues growing pot indoors. You should place an exhaust fan near the top of the growing room to remove warm air along with a filtered air inlet on the opposite side of the inlet near the floor. Temperatures should be maintained between 70 and 85 degrees when lights are on and 58 and 70 degrees when they are off. This may vary slightly depending on your cannabis strain.
Because of these variations, the size of the exhaust fan needed to grow pot indoors will depend on the size of your grow space and type of lighting. You may need to test your ventilation system once you set up your lights – this will allow you to see how much airflow you need in order to maintain a comfortable growing temperature for your plants. In addition to maintaining proper temperature, it’s also recommended that you install a circulating fan to add a light breeze and prevent pests and mold from targeting your plants.
Design, Set Up, or Purchase Other Necessary Equipment
You’re not quite done yet! There are some other pieces of equipment that you need to purchase and install.
Your light timer is important, as it will regulate your light and dark cycle. Usually, you will need to have your plants on for about 16 to 20 hours during each 24 hour period during the vegetative growth and then switch to 12 hours of light during blooming. The accuracy of your light timing is important because you risk stressing your plants otherwise.
You will also need a well-regulated thermostat to monitor your temperature for 24 hours a day. You can use a timer for this or purchase a thermostat switch. This will keep your temperature from rising above a preset level, saving energy and maintaining a consistent temperature.
You will also need a hygrometer to keep track of the humidity level in your grow room. If you want to save some money, you can buy a combination thermostat/hygrometer.
pH Meter or Test Kit
The type of container that you are growing weed indoors in will depend primarily on the size and type of your plants, the system you are using, and the growing medium. If you are growing in a hydroponic system, you might use a tray-style flood-and-drain set-up that consists of small net pots filled with clay pebbles or even a piece of rockwool. You can grow lots of small plants in this kind of setup. However, if you are using a soil-based grow, you may need to incorporate lots of 10-gallon nursery pots for large plants.
You don’t need to break the bank when buying containers for growing cannabis plants indoors. Instead, choose some inexpensive options like cloth bags or five-gallon buckets. Just make sure the option you choose has adequate drainage, as these plants are very sensitive to becoming over waterlogged.
Decide on Soil vs. Hydroponics Growing Medium
Growing weed indoors will give you multiple methods of soil to choose from. There are two primary types of growing medium – soil and hydroponics.
Soil is the most common way that people grow weed indoors, largely because it mimics the natural environment of your plants and makes it more forgiving or inexperienced growers. You can use any potting soil as long as it doesn’t contain artificial extended release fertilizers. You can also make your own organic soil that has already been fertilized. This will allow you to grow your plants without adding any additional nutrients later on. You can purchase this premade or make your own with worm castings, bat guano, and other high-quality natural materials.
If you’re growing plants organically in soil, you will need to have a healthy population of microorganisms like bacteria and mycorrhizae to switch organic matter into usable nutrients.
Your next option is hydroponics growing. Many indoor growers are considering hydroponic media for growing cannabis indoors, as it allows for quicker nutrient uptake. You need to be more precise, as you’ll have to feed concentrated solutions of nutrients to be absorbed by the plant’s roots via osmosis. However, you can use multiple different materials in your hydroponic solution, including:
- Expanded clay pebble
- Coco Coir
In many cases, commercial soilless mixes will contain several of these ingredients for the best possible blend. You can use them in automated hydroponic units or in individual containers that you water by hand.
Start Your Seeds and Care For Your Seedlings
Now, the part that we’ve all been waiting for – it’s time to choose your seeds and to find a seed bank that ships to the USA! Choosing a strain of marijuana is one of the most important considerations you will need to make. Each plant is different and has different requirements for growing conditions.
Sativa plants, for example, are tall and put out smaller buds. Kushes or cookie indicator strains, like hybrid and indicator plants, are bushier and give you fatter buds. Consider the size of your plants, your grow room size, and your lighting availability before you decide on your plants.
You also need to consider your ideal yields. Do you want your harvest to consist of small or fat buds? How much yield do you want to get out of a single plant?
Thinking about long-day plants and short-day plants is also a consideration to make. Short day plants require lots of darkness and short periods of light, while long-day plants are the exact opposite. Flowering times also come into play, because some plants take longer to grow in flowering stage. If you don’t know exactly how long your plants are going to flower – or how long the light length needs to be – you are going to get yourself into trouble.
When you first start out growing weed indoors, you will also need to choose between seeds and clones. Seeds are great for novice growers because they are the source of all genetics and help you feel closer to your plants. You can hone in on the particular traits of a strain that you really like, and you can even enhance or breed the strain at home if you decide to do os. This can also lead to more disease- plants.
Clones, on the other hand, are better at showing quick results. When you pick clones over seeds, you will have a stronger plant that will have a preset sex. You don’t have to worry about wasting seeds because you accidentally grew males, and the clones are already on their way to becoming fully grown adult plants. They offer a faster turn-around time, too.
Fertilize and Water Your Plants
If you are growing cannabis indoors, you are going to need to add lots of fertilizer. These plants require more fertilizer and more nutrients than other types of plants. Generally speaking, your plant is going to need the three main macronutrients – nitrogen, phosphorous, and potassium, usually marketed and sold commercially as NPK.
In addition, your plants will need small quantities of micronutrients like magnesium, copper, iron, and calcium.
If you decide not to use a pre-fertilized soil mix for your plants, you will need to feed your plants once a week at a bare minimum. Fertilizers are usually sold in powder form or as concentrated liquid. Often you will need to mix them with water and they will be sold separately for flower and vegetative growth. This is because your plant has different nutrient needs during different stages of its life cycle.
When you’ve purchased the nutrients you need, you can mix them with water if required and water your plants with the solution. Start at half strength when you’re just out – it’s very easy to burn your plants with too much fertilizer. Begin by fertilizing just once a week or once every other week until you figure out the signs of nutrient deficiencies in your plant – it will be far worse to fertilize your plant when it doesn’t need it than to under fertilize it.
Watering is also important, but you need to think carefully about its origins. If you live in an area that has treated water, you need to be careful about filtering the water before you put it on your plants. High levels of chlorine or other dissolved minerals can harm your plants or even build up in the root zone to affect the uptake of nutrients. Some water can even contain pathogens or fungus that can cause root disease.
Try not to overwater your plants, taking extra caution to only give your plants the water they need and nothing more. Cannabis plants are prone to fungal rot when they get too wet, especially if there isn’t adequate ventilation. You will need to consider the size of your plants, the temperature of the room, and the medium used before you water. It’s not risky to wait until the leaves of your plant have just begun to droop to water, either.
Harvest Your Finished Product
This is the absolute best part about growing weed plants indoors – harvesting your plants. Once your plants are ripe, it will be time to cut them and dry them.
To determine whether your plants have ripened, you will need to wait for about three months. Plants generally don’t ripen until about two to three months into the flowering stage. Be patient and let the buds develop – all you need to do is provide fertilizer and water. When the marijuana plants are ripe, most of the white hairs will have turned brown and your plant growth will have slowed. They will be releasing heavy odors and the buds will be hard and compact.
Start by chopping your plants branch by branch or by cutting the entire plant. Remove any excess fan leaves from the branches and between the buds. Dry them at 70 degrees and 50% humidity, either by using a drying rack or just clothespins and hangers. Hang your plants upside down until they are dry – this usually takes at least three days but often takes up to a week. They will feel dry to the touch when finished.
Then, it’s time to cure. Curing buds is one of the most important steps in growing marijuana as it helps break down chlorophyll and encourage helpful bacteria. You need to make sure your buds are fully dry to do this to prevent mold on the buds. Keep the curing room at the same temperature as you did when the buds were drying, but raise the humidity slightly to about 65%. You want your plants to retain a small amount of water to add terpenes and make for a smoother user experience.
Place your buds in glass jars and fill them about three-quarters of the way full. Each day for a few weeks, let the jar breathe for about two hours. Leave the buds in the jar for a few weeks.
This may sound like a lot of information as you are beginning in your endeavors to grow pot indoors – and to be fair, it really is! However, as you get started growing marijuana indoors, you will be able to adapt your equipment, grow room, and techniques to fit your specific needs and preferences. By getting started on the right foot, you’ll have a solid foundation and be able to grow marijuana indoors seemingly in your sleep – that’s how seamless and simple it will be!
Read More: Highest Yielding Strains in 2020