How to grow marijuana indoors
How to grow marijuana outdoors: a beginner’s guide, Growing weed indoors is great because you can grow it any time of year and you’ll have complete control over the plant and what you put into it. Live in an apartment or a small house? Don’t worry, you can grow weed practically anywhere, even if you don’t have a backyard or a lot of extra space.
Benefits of growing weed indoors
Although it’s more resource-intensive than growing outdoors and you will likely have to spend more money on utilities to power equipment, you can control every aspect of your grow environment and what you put in your plant, allowing you to dial in your setup to grow some primo weed.
Unlike outdoor growing, you aren’t tied to the sun and the seasons. You will be providing the entire environment the plants need to grow, including the grow medium—soil, rockwool, etc.—and regulating the amount of water and nutrients they receive, as well as controlling temperature, humidity, and more for them.
You can let your plants get as big as you want, and can control when they flower and when you harvest, and you can start another batch right away or whenever you want. You can grow any time of year, even straight through winter or summer, and you’ll get consistent crops each time.
Privacy and security
Even in legal states, you may want to conceal your crop from judgmental neighbors and definitely from potential thieves. Growing indoors allows you to grow discreetly behind a locked door.
How to set up an indoor grow room
Below is a list of things to consider and equipment you will need to purchase to get started growing marijuana indoors.
You’ll need a dedicated space for your marijuana plants—you won’t be able to move them around. Ideally, the space is next to a window so you can vent air from the grow space outside. Growing weed plants smell! Especially when flowering kicks in, you’ll want to redirect air so your house doesn’t reek of weed.
A lot of people these days buy grow tents for their weed, but they aren’t necessary. You can grow in a closet, tent, cabinet, spare room, or a corner in an unfinished basement. Just keep in mind that you’ll need to tailor your equipment (and plants) to fit the space.
It’s a good idea to start small—the smaller the grow, the less expensive it is to set up. Newbie mistakes will be less costly if you only have a handful of plants. Additionally, most state laws only allow for growing six plants, but some allow up to 12.
When designing your space, you’ll need to take into account room for your plants, as well as space for lights, fans, ducting, and other equipment. You’ll also need space to work on the plants. Cannabis plants can double in size in the early stages of flowering, so make sure you have adequate head space!
Every space is different and there will be a learning curve to growing in yours.
Cannabis, like all plants, prefers certain environmental conditions in order to thrive. Temperature, humidity, light intensity, and airflow are all factors that will need to be monitored and regulated in order to keep cannabis healthy through its different phases.
Although you’ll be controlling the climate inside the grow space, climate outside the grow space will affect your plants. If the environment outside your grow space is very warm or humid, you’ll have issues controlling your grow space. Choose a cool, dry area with ready access to fresh air from outside.
If you’re growing in a cold, wet basement, you might have to run a dehumidifier or heater to stabilize the environment. Conversely, if your space is too hot, you might need to add extra fans or an AC to cool the plants down.
One trick to avoid hot temps is to have the grow lights on during the evening, when it’s cooler outside, and leave the lights off during the day when it’s hot. This may help bring down the temps, but you’ll only be able to work on the plants at nighttime when the lights are on.
Weed plants need different amounts of light during their vegetative and flowering stages. You don’t have to worry about this in an outdoor setting—the sun and the season dictate this—but when growing indoors, you will be controlling it.
Plants need 18 hours of light a day when in the vegetative stage and 12 hours a day when flowering. The reduction in light from 18 to 12 hours a day is what triggers the flowering cycle—when weed plants start to grow buds.
Because the amount of light a plant receives is so important, you’ll need to make your indoor grow space light-tight. Light leaks during dark periods will confuse your plants and can cause them to produce male flowers or revert to a different stage.
Different lights produce different colors of light. Here’s a brief rundown of the most popular types of cannabis grow lights used for indoor growing.
Can you grow weed indoors without grow lights?
Just about all indoor weed growers use grow lights for their plants. Grow lights ensure your weed plants will grow healthy and strong, while maximizing yields.
In theory, as long as a cannabis plant can get at least 6 hours of full sun a day, whether inside next to a window, or outside, you don’t necessarily need a grow light, but pretty much all indoor growers use them.
HID (high-intensity discharge) lights are the industry standard, widely used for their combination of output, efficiency, and value. They cost a bit more than incandescent or fluorescent fixtures, but produce far more light per unit of electricity used. Conversely, they are not as efficient as LED lighting, but they cost much less.
The two main types of HID lamp used for growing are:
- Metal halide (MH) produces light that is blueish-white and is generally used during vegetative growth.
- High pressure sodium (HPS) produces light that is more on the red-orange end of the spectrum and is used during the flowering stage.
In addition to bulbs, HID lighting setups require a ballast and hood/reflector for each light. Some ballasts are designed for use with either MH or HPS lamps, while many newer designs will run both.
If you can’t afford both MH and HPS bulbs, start with HPS as they deliver more light per watt. Magnetic ballasts are cheaper than digital ballasts, but run hotter, are less efficient, and harder on your bulbs. Digital ballasts are generally a better option, but are more expensive. Beware of cheap digital ballasts, as they are often not well shielded and can create electromagnetic interference that will affect radio and WiFi signals.
Unless you’re growing in a large, open space with a lot of ventilation, you’ll need air-cooled reflector hoods to mount your lamps in, as HID bulbs produce a lot of heat. This requires ducting and exhaust fans, which will increase your initial cost but make controlling temperature in your grow room much easier.
Fluorescent grow lights
Fluorescent light fixtures, particularly those using high-output T5 bulbs, are quite popular with small-scale cannabis growers because:
- They tend to be cheaper to set up, as reflector, ballast, and bulbs are included in a single package.
- They don’t require a cooling system since they don’t generate nearly the amount of heat that HID setups do.
The main drawback is fluorescent lights are less efficient, generating about 20-30% less light per watt of electricity used; space is another concern, as it would require approximately 19 four-foot long T5 bulbs to equal the output of a single 600 watt HPS bulb.
LED grow lights
Light emitting diode (LED) technology has been around for a while, and they are getting more efficient all the time. The main drawback to LED grow lights is their cost: well-designed fixtures can cost 10 times what a comparable HID setup would.