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How To Grow Marijuana Indoors

Whether you’re a beginner or a seasoned stoner, you can grow your marijuana indoors successfully if you:

  • Know how to choose the right strain
  • Learn how to set up your indoor grow area properly, and
  • Commit to caring for the plant throughout its growth cycle

Here’s an A-to-Z guide to help you grow high-quality kush indoors, from seed to harvest. You’ll be able to reap, roll, and light up your joints in just a few months!

THE BENEFITS OF GROWING CANNABIS INDOORS

Growing cannabis indoors has several benefits over growing it outdoors, including:

Faster Harvest Time

Depending on the strain you go with, you can go from seed to getting high on your first harvest within 3 to 4 months. That’s a few months less than it would take you to grow marijuana outdoors.

Flexibility

Unlike growing outdoors where the environmental conditions fluctuate and you can’t control the situation, indoor growing lets you control all aspects of cultivating your plant. You can plant all year round without worrying about the weather or seasons.

Highly Potent Weed

Having complete control of the entire indoor growing process allows you to optimize the conditions so your plants reach their maximum potential. You can provide the right amount of water, light, and nutrients to get plants with denser nugs, higher trichome count, and better THC levels for a long-lasting high.

Regular Supply

Because it takes less time to grow marijuana indoors and you can do it throughout the year, you’ll have multiple harvests (3 – 4) within a year. This ensures you get a consistent supply of the exact quality of weed you need to meet your needs. It’s different from growing outdoors, where you’ll only have one harvest after 8 – 9 months.

HOW TO GROW WEED INDOORS (5-STEP GUIDE)

Like most plants, marijuana needs tender care to go from seed to bud. You need to give your plants the right amount of resources they need to thrive at various stages of their growth. These include water, nutrients, light, temperature, and ventilation.

Follow our five-step indoor marijuana growing process to get high yields of top-shelf buds:

Step 1: Choose A Strain

Choosing the right strain to grow depends on the effect you’re after.

  • Indica: If you’re looking for deep relaxation that washes over you and blissfully transports you to the clouds and back, without the mental ‘buzz’, go for indica. It’s simple to cultivate and often grows shorter and bushier (usually about 2 to 4 feet tall). This makes it ideal for growing indoors, especially in small spaces.
  • Sativa: For an energizing, mental high, settle for sativa. You’ll experience the tingles in your head, but still be able to think and get work done. Sativa plants grow taller than indica strains. So, be prepared to put in more effort to grow them indoors.
  • Hybrid: Get a well-bred hybrid of indica and sativa for a more balanced experience of both worlds. You’ll enjoy full-body relaxation combined with the psychedelic it’s-great-to-be-alive type of euphoria most people have when smoking pot.

Photoperiod Vs Auto-flowering Strains

Another thing to pay attention to when picking a strain is whether they are photoperiod or auto-flowering strains.

Photoperiod strains require your input through light regulation to get to the flowering or budding stage, while auto-flowering strains produce flowers on their own.

You won’t have to maintain a strict lighting schedule if you choose an auto-flowering or ruderalis strain. However, you must be keen to get a strain with the correct chemical composition to grow great weed.

The CBD-to-THC ratio of typical ruderalis plants is usually not enough to give the relaxed, floating, or euphoric effect indicas or sativas produce. You can, however, get auto-flowering strains that have been hybridized with sativa or indica, to increase potency.

Step 2: Choose Your Indoor Grow Space

After you’ve chosen your strain, choose where you’re going to grow your marijuana plants. You can grow marijuana anywhere – in your closet, garage, spare room, grow box, or grow tent – provided the area has the following key features:

  • Enough space. The space must be tall and wide enough to accommodate the size and number of plants you’d like to grow. Most states limit the number of plants home herb growers should plant. So check your state recommendations to confirm what your limit is.
  • Reflective or white interior surroundings, including your interior walls, ceiling, and floor. You don’t want your grow space to absorb any light. It should reflect all light back into the room instead, so your plants can absorb as much light as they need to grow.
  • Light sealed. You also don’t want any light from outside to penetrate the growing area, especially during the flowering stage. Marijuana requires hours of pitch-black darkness to flourish at this stage.
  • Openings for installing ventilation fans.
  • A waterproof tray or floor drain to catch and direct spills away from the plants.
  • Proper wiring to install your lighting system the right way.

If you’re a first-time grower, we recommend using a grow tent. It’s easier to set up a grow tent in your spare room than to convert a space like a closet into a growing area.

Grow tents are designed for growing cannabis indoors. They have reflective walls, are lightproof, and contain built-in options to help you create optimum conditions for growing healthy plants.

Step 3: Set Up Your Grow Space

To set up your grow space correctly, first gather all the equipment you’ll need. The most essential must-have tools include:

  • Lights: Grow lights produce varying quality and intensity of light. If you want high yields, go with high-intensity discharge (HID) bulbs, preferably metal-halide (MH) and high-pressure sodium (HPS). You’ll require the MH light during the plant’s vegetative stage, then switch to the HPS light at the flowering phase. But, if your goal is higher terpene concentration to maximize the entourage effect and produce great weed, then get light-emitting diode (LED) bulbs or ceramic metal halide (CMH) bulbs.
  • Fans, including intake and extractor fans, for proper ventilation and air circulation.
  • Planting pots to hold and support your plants.
  • Timer to automate various processes taking place in your grow room.
  • Thermometer and hygrometer for monitoring your grow space’s temperature and humidity.

Once you have your equipment, set up your indoor grow system with air flow and lighting.

Setting Up Your Air Flow System

When growing marijuana outdoors, air moves around the plants naturally. You’ll need similar airflow to grow your supply indoors.

There are two things you need to focus on to ensure proper airflow and create the best indoor growing climate: ventilation and circulation.

Ventilation supports the movement of air into and out of the room. It cleans the air. Circulation, on the other hand, encourages air movement within the room, promoting CO2 uptake.

Ventilation

For proper ventilation in your grow space, install your intake and extractor fans strategically.

Place the extractor fan near the top on one end of the room and the intake fan of a similar size, at the bottom, on the opposite end. This way, the extractor fan will take stale air out of your grow room while the intake fan introduces fresh air.

Most ganja farmers use in-line duct fans. They’re the easiest to install. You simply connect a flexible duct pipe to any holes you’ve made.

If using a grow tent, measure the size of the existing intake and exhaust holes and purchase 4-, 6-, or 8-inch diameter fans to match.

Also, consider installing a filter on your intake duct to prevent contaminants, like mold spores and bugs, from entering the room.

The idea is to get enough clean air, replacing all the air inside your grow area once every minute. You can also place a carbon filter on your exhaust duct to mask that classic weed smell. You know how strong the aroma of premium herb is, especially when flowering! Carbon filters will prevent the scent from seeping out of your grow room.

Circulation

Place more fans inside to circulate the air almost evenly around the grow room. This will ensure any oxygen surrounding your plants is replaced with the carbon dioxide the plants need to bloom.

For maximum air circulation, put two small fans, one on opposite sides or corners of the room. Ensure the fans are at an angle (not facing your plants directly) to avoid wind burn. You’ll have to reposition them occasionally as your plants grow.

Setting Up Your Lighting System

Mount your lights above your plants for equal light distribution over your entire canopy. Use hooks, strong ropes, or chains to hang your light fixtures on your grow room’s ceiling. Ensure you can easily lower or raise all lights because you’ll have to adjust them as the plants get taller.

Place them near the top of your plants, but not too close to avoid heat stress.

Also, connect your entire lighting system to a timer to automate their on-off cycle and make your work easier.

Step 4: Germinating, Planting & Caring For The Plant

First, select the medium you’ll use to germinate and nurture your weed to maturity. You can work with soil or opt for a soilless medium like coco coir and perlite. You could also work with a hydroponics system.

Using soil will give you the best-tasting buds. It’s also the easiest way to grow ganja indoors, provided you get high-quality potting soil with no artificial extended-release fertilizer. Soils with slow-release nutrients will prevent proper budding at the flowering stage.

With soil as your medium, the rest of the process becomes straightforward. You can germinate your seeds directly in the soil instead of using a seedling plug or starter cube. To do this, place your soil in relatively big fabric pots. Then plant your seeds about 0.5 to 1 inch deep (almost a knuckle deep). One seed per pot is enough.

Avoid using small pots even if the seeds look small. You want your plant to have enough space to grow without being root bound. As long as you keep the soil warm and moist during germination, your cannabis seedlings will sprout within 3 to 7 days.

After that, it’s all about nurturing and caring for the plant as it moves from the seedling stage to the vegetative and, finally, flowering or budding stage. You’ll have to adjust the lighting, temperature, and nutrients you provide at each stage to produce a premium product.

Lighting Requirements For Growing Cannabis Indoors

At the seedling stage, your plants need 18-24 hours of light. Maintain this light cycle until your plants develop full fan-like leaves and enter the vegetative stage.

In the vegetative stage, switch to an 18-hour day and 6-hour night light cycle. The 18/6h cycle helps your plants’ stems get thicker and taller as they produce more branches, leaves, and nodes.

Depending on the strain you’ve grown, you’ll notice your plants begin to take shape. This stage can take 4 to 8 weeks or more, until you change the light cycle to induce flowering when growing photoperiod strains.

It’s best to keep your plants in their vegetative state for a while to maximize yield. With a slightly longer vegetative period, one plant can grow and cover several square meters, so you harvest more from it. You’d get a decent yield from just a few plants that have grown well.

To bloom, cannabis plants require a 10-12 hour day and 12-hour night light cycle. The night cycle must be 12 hours of total pitch-black darkness. If any light leaks into your grow room during this time, it will interfere with the flowering process and might stop it. Your plant might even go back to the vegetative state.

Important note: The 12-hour light cycle is a requirement for the photoperiod strains only. Auto-flowering varieties don’t need 12 hours in the dark to produce flowers.

Temperature Requirements For Growing Cannabis Indoors

During the vegetative state, your plants require between 75 and 80°F (about 23.9 to 27 °C) and a relative humidity of 60-70% to thrive.

At the flowering stage, the temperature requirements reduce slightly to 65 and 80°F (about 18 to 26 °C). The relative humidity needed also reduces to 50-55%.

Monitor your temperature and humidity frequently then adjust your airflow and lighting systems to maintain the required growing climate.

Nutrient Requirements For Growing Cannabis Indoors

The right soil often has the nutrients your plants need to grow. But you can add more nutrients in liquid form when watering your plants to maximize growth.

In limited amounts, add nitrogen during the vegetative stage to promote photosynthesis and enhance rapid growth. It will help your plants branch out more. When you get to the flowering stage, reduce nitrogen and provide phosphorus to help with the development of buds.

Other nutrients you may need throughout your plant’s growth cycle include:

  • Potassium – enables your plant to fight off disease and stay healthy
  • Calcium – helps your plant withstand stress, like heat, and gives it structure

Watering Your Marijuana Plants

Water your weed plants regularly so that they can take in all the nutrients and minerals from the soil as they need to. Be careful not to overwater your plants, though. The roots will drown and fail to absorb nutrients, leading to nutrient deficiencies.

The right watering schedule depends on the drainage of your growing pots. For fabric pots, watering once every 2-3 days works well.

You have to be more careful when handling small plants in big pots. Their roots ‘drink’ water at a slower rate and could drown faster. You might have to water them less frequently. To see whether your plants need water, dip your index finger about an inch into the soil and check if it’s dry.

Common Pests And Diseases Of Indoor Cannabis

Some common pests you might have to deal with when growing weed indoors include thrips, aphids, spider mites, and fungus nuts. These mostly attack your leaves, but they could also attack your pre-flowers and buds.

You might also notice your leaves turning color:

  • Yellow leaves indicate the presence of mold or bud rot
  • Brown spots signal calcium deficiency
  • Dark leaves with a bluish-purple undertone show copper deficiency

Discolored leaves could also be a sign of root rot. Inspect your plants regularly to identify and deal with any problems early enough.

Step 5: Harvesting

After the minimum two months required for the flowering phase, you’ll know whether your plants are ready for harvesting by looking at the color of the hairs or trichomes.

If most (50-70%) of the white hair-like structures have darkened or the trichomes are cloudy/milky, they’re ready. Harvesting at this point will give you the highest levels of THC for great pain-relieving and euphoric effects.

If you prefer less THC and more Cannabinol (CBN), wait until the cloudy trichomes turn amber, or at least 70-90% of the white hairs darken. You’ll experience a more relaxing, anxiety-reducing effect with the heavy ‘couch potato’ stony feel when you do this.

Next, cut your plants into small sections and hang them to dry for 7-14 days. Place them upside down in a cool, dark area with enough ventilation for proper drying. This helps to remove the grassy smell of freshly harvested buds, allowing the weed’s aroma and flavor to re-emerge.

CONCLUSION

Growing marijuana indoors requires some effort, but the results are worth it. You’ll always produce the highest-quality pot if you choose high-grade seeds and follow a proven process.

If you have any questions about growing marijuana indoors, contact us. We’re always ready to help!

You may also want to check out our products to meet your medical or recreational needs. From pre-rolls and fresh flower concentrates to edibles, topicals, beverages, and vapes, we’ve got great supplies and great deals to match.