Ultimate 10-Minute Cannabis Indoor Grow Guide

Last updated Mar 25, 2024

by Nebula Haze

This tutorial is Part 2 of our “how to grow weed for beginners” series:

Part 1: Get Your Cannabis Grow Supplies > Part 2: Seed-to-Harvest Grow Guide

This 10-minute tutorial teaches you how to grow cannabis indoors once you have your equipment (see Part 1 to get the necessary tools for a productive cannabis garden). Follow all 5 steps in today’s tutorial and you will harvest superior weed even if it’s your very first grow. Growing weed at home lets you keep yourself safe, save money, and get better quality buds than most people can buy.

Other helpful resources:

 

 

Table of Contents

Step 1: Get Set Up

Step 2: Germinate Your Seeds

Step 3: Vegetative Stage – Only Stems and Leaves

Step 4: Flowering Stage – Buds Start Growing!

Step 5: Harvest, Dry, and Cure Buds

 

 

10-Minute Cannabis Grow Tutorial

Step 1: Get Set Up

Once you have these items, you’re ready to start growing weed indoors.

  • A place to grow (for example a closet, grow tent in a room, a spare room, or garage/attic/cellar)
  • Grow light (LEDs recommended for most beginners and indoor grow situations)
  • Grow medium (soil, coco, or hydro)
  • Cannabis-friendly nutrients (nutrients improve yields, growth rates, and bud potency)
  • Seeds or Clones

Want a quick crash course? Read the 10-minute guide to setting up to grow indoors: https://www.growweedeasy.com/indoor-setup

I recommend beginners get a grow tent (usually under $100) to create a waterproof, light-proof, reflective, portable, “pop-up” grow area with a bar to hang your grow light and help protect plants from bugs or spiders. Grow tents also give you the ability to prevent any smells from leaking out if you set it up with a carbon filter. A grow tent is much cheaper and easier to set up than creating a comparable space from scratch.

Grow tents come in many sizes.

Cannabis grow tents - a 2'x2'x3' grow tent on left and 2'x4'x5' grow tent on right

Additional resources:

 

Step 2: Germination & Seedling Care

The easiest and most simple way to germinate is to plant your seed directly in the grow medium. Just like in nature. Another common option is to germinate seeds in a seedling plug, then plant the whole plug after germination (if growing in hydro, you should always use a seedling plug).

Cannabis seeds often appear dark brown with tiger stripes. However, that outer coating can rub off and the seeds are tan underneath. Tan vs dark seed color is not a sign of quality.

Example of viable cannabis seeds - even the pale one!

Cannabis Germination Tips

  • Plant seed about a half knuckle deep (1/2″ or 1.5 cm)
  • Seeds usually take 1-7 days to germinate (2-4 days average)
  • Keep moist but not soaking
  • Germination goes much faster when seeds are warm
  • Never let seeds dry out!

Note: Older seeds germinate slower and often have lower germination rates. Even with fresh seeds, some strains germinate better/faster than others.

Place seed about a half-knuckle deep

Watch a quick gif animation showing the planting of a cannabis seed for germination, then patting the soil down gently

Keep moist and warm until seedling appears

Example of a happy young cannabis seedling

How to water seedlings

Many beginner growers accidentally overwater their seedlings, which causes slow growth, droopiness, and nutrient deficiencies. Here’s how to water cannabis seedlings properly.

  • Give 2 cups (500ml) water per seedling at first
  • Pour water slowly in a small circle around the base of the seedling. I first pour my water into a cup so it’s easier to pour water around each seedling.
  • The water circle should be ~2 inches (5 cm) in every direction from the base of your seedling
  • Don’t give water again until the top part of the soil is mostly dry
  • As your seedling grows, slowly ramp up the water amount so the circle around the base is always about the width of the leaves
  • Each grow medium and environment is different, which changes how much water your seedlings drink. On average, seedlings need to be watered every 2-3 days

Note: If growing in coco or hydroponics, you need to give nutrients in the water from the beginning (coco and water don’t contain nutrients). With potting soil, you don’t need to give nutrients for several weeks while the plant uses up the nutrients in the soil. With a super soil setup, you don’t ever provide extra nutrients because this type of soil has been designed to “slow release” organic nutrients over the course of the grow.

Water seedlings slowly in a circle around the base of the plant. Give 2 cups (500ml) water per seedling at this stage.

Here’s an example of watering a marijuana seedling

Slowly increase the amount of water as the seedling grows. Try to get the water circle around the width of the leaves

Additional resources:

 

Step 3: Vegetative Stage – Only Stems and Leaves

Now that you’ve got a growing cannabis plant, you’re officially in the “vegetative stage” of your plant’s life. During this first stage of life, plants will grow stems and leaves, but no buds. Plant care is almost like a regular houseplant in this stage.

How to care for vegetative cannabis plants:

  • Water plants regularly (or maintain the water reservoir if in hydro)
    • If using nutrients, add nutrients according to directions for the vegetative stage
  • Periodically adjust grow light to keep it the recommended distance from plants as they grow
  • Watch out for problems like discolored leaves or droopiness
  • Enjoy their beauty

In the vegetative stage, a cannabis plant can recover from a lot even if you mess up. It’s kind of like the “training wheels” stage of growing weed. Your main job is simply to water your plants and make sure they’re getting the right amount of nutrients and light. If using high levels of nutrients and supplements, try to give plain water sometimes to prevent nutrient build-up.

Note: Auto-flowering strains of cannabis have a short vegetative stage. These plants automatically start making buds about 3-6 weeks from germination. Learn more about auto-flowering cannabis strains.

Cannabis plants in the vegetative stage only grow stems and leaves, no buds!

Cannabis plants in the vegetative stage under a 315 CMH grow light

 

How to water plants

By the time your seedling is a few weeks old (5+ sets of leaves), it should have an established, healthy root system that can handle more water at a time. At this point, switch to normal watering practices:

  • Give enough water that you get a little bit of runoff out the bottom
  • Remove any runoff (never let plant roots sit in water)
  • Wait until the top inch (up to your first knuckle) feels dry to the touch
  • Repeat

If plants dry out in less than 2 days, it means you should give more water at a time (or they may have overgrown the pot). If they take more than 3 days to dry between waterings, give less water at a time until they’re drinking more.

Nutrients (if you’re using them)

  • Follow the nutrient schedule or recommended dosage for “vegetative” growth
  • It’s a good idea to start at half-strength at first since most nutrient recommendations are too strong for marijuana plants
  • Only raise the nutrient dosage if you notice plants are looking pale or lime green, which are signs the plant needs higher levels of nutrients overall
  • Typically you’ll only use full-strength nutrients under strong grow lights with healthy fast-growing plants

When to switch to the flowering stage

Once your plant has reached half the final desired size, it’s time to move on to the next step. Otherwise, your plants keep getting bigger and bigger.

Plants typically double in size during the next stage of life. That means you should move on to the next step once plants have reached half the final desired height

Additional resources:

 

Step 4: Flowering Stage – It’s Bud Time!

When your plant has reached half the final desired size, it’s time to start making buds. This stage of life is known as the “flowering stage”.

  • The flowering stage should be initiated when your plant has reached half the final desired height. Plants often double in size after they start flowering, so don’t wait too long!
  • Initiate the flowering stage by putting grow lights on a timer with a 12/12 light schedule (12 hours off, 12 hours on)
  • Make sure the plant gets total darkness during the dark period or it won’t make buds. Ensure the grow space is totally light-proof without any light leaks
  • The first few weeks after the switch to 12/12, your plant will be growing fast. This extra-fast growth period is known as the flowering stretch.

This daily dark period is like a message that tells your plant that winter is coming. Plants will typically start growing buds within 2-3 weeks after the switch to a 12/12 light schedule.

In order to get a cannabis plant to enter the flowering stage and start making buds, a grower needs to use a timer to put the grow lights on a 12/12 light schedule (12 hours light, 12 hours darkness)

Flowering stage care:

  • If using nutrients, now is the time to switch to “bloom” nutrients.
  • Other than the 12/12 light schedule and using flowering nutrients, plant care is basically the same as it was in the vegetative stage
  • When your plant starts flowering, you need to double-check that it’s making female flowers (buds) and not male flowers (pollen sacs). You can skip this step if you started with feminized seeds since all plants will be female.

Note: “Bloom” and “flowering” mean the same thing when it comes to cannabis plants. Buds are the flowers of the cannabis plant.

Buds should start growing within 2-3 weeks of initiating 12/12

Male vs Female Identification 

  • Female flowers look like wispy white hairs at first. These eventually fatten into the buds we know and love
  • Male plants grow pollen sacs that look like bunches of grapes
  • Pollen sacs aren’t good to smoke and if the pollen is released it make your buds grow seeds
  • Unless you want seeds, it’s recommended to remove male plants on sight, before their pollen sacs open up

Identify male plants as soon as possible and separate them to prevent seedy buds.

Male cannabis plant (does NOT grow buds) - most growers throw away male plants on site Female cannabis plant (DOES grow buds) - female plants grow the sensimilla / buds that every cannabis grower is trying to produce

 

Flowering Stage Tips

  • Watch plants closely and react quickly to any problems so you cruise to the finish line
  • Most plants stop growing taller around 5-8 weeks after 12/12 starts, but buds still need time to fatten and reach peak potency
  • It’s hard to be patient while buds fatten and mature. It might seem like buds are ready to harvest once plants stop growing vegetatively. But even though you might not see it, buds are getting bigger and more potent each day.
  • Most plants are ready to harvest about 8-12 weeks after the switch to 12/12 though some strains take more or less time.
  • In the next step, you’ll learn how to determine when your plant is ready to harvest

A female plant starts by growing wispy white hairs where buds will form.

Buds take a while to slowly fatten into buds.

Most strains are ready to harvest 8-12 weeks after initiating 12/12 (the length of time is mostly dependent on the strain)

A bountiful harvest!

Additional resources:

 

Step 5: Harvest Your Cannabis

When plants are ready to harvest, the white hairs on the buds will have darkened and will have mostly curled in.

Examples of marijuana buds that are ready to harvest. Every strain looks a little different.

You can choose when to harvest your buds based purely on how they look, but you need to look at buds under a magnifier to most accurately determine when they’ve reached peak potency. This is done by looking at the “trichomes” or glitter that grows on buds at high magnification. When buds have reached the highest levels of THC the heads of trichomes turn milky white. Waiting until a few trichomes turn amber/yellow can give buds more of a body or relaxation effect.

When trichome heads look milky white under magnification, the buds have reached the highest level of THC and other cannabinoids

Additional resources:

 

Dry & Cure Your Buds

What’s the “magic ingredient” that makes buds burn smoothly, get white ash, smell dank, and feel as potent as possible? A proper dry & cure! Drying and curing buds can increase their quality by up to 50% or more compared to improperly drying or not curing.

Air-Dry Buds by Hanging Them Upside Down (this is the most popular drying method)

  • Cut off branches and remove all the big fan leaves.
  • Hang buds upside down in an enclosed space like a grow tent or a closet.
  • Monitor temperature and humidity for best results.
    • Ideal temperature: 60-70°F (16-21°C) <– Focus on this if possible
    • Ideal humidity: 60% RH
    • If humidity is too low, dry buds by hanging them from inside a large cardboard box. This creates a humid pocket around the buds.
    • If humidity is too high, mold is a concern. Consider using a dehumidifier or possibly a drying aid like the HerbsNow.
    • Cold temperature (keeping buds cold but not freezing) during air-drying lowers the chance of running into problems.
  • Gentle air circulation
  • Buds should have a little bit of space between them. They are more likely to grow mold if they’re touching.
  • Buds are done drying when small stems snap instead of bend, and buds pop off cleanly without strings.
  • Drying usually takes about 4-10 days depending on the environment and thickness of buds

Curing

  • Once buds are dry, trim away extra leaves
  • Then put the newly-trimmed buds in quart-sized glass mason jars filled about 80% full
  • Open jars once a day to let in fresh air and make sure the buds don’t feel wet or stick together
  • Use a mini hygrometer to monitor humidity. Ideal humidity is 55-62% RH
  • Add a “Boveda” or “Boost” humidipak to jars if desired. These automatically maintain the proper humidity for curing.
  • After the first 2 weeks, you can open jars once every few days, and slowly taper off to less often
  • Curing is considered done after 2 weeks, but the quality (and perceived potency) of buds may continue to improve for up to a few months.
  • Some strains benefit more from a long cure than others.

Example of a cannabis harvest in quart sized mason jars. From this picture you can assume the grower harvested about 6 ounces of bud.

Use a mini hygrometer to monitor humidity

Example of a hygrometer to report the humidity inside a cannabis curing jar

Use a “Boveda” or “Boost” humidipak to automatically maintain humidity in the 55-62% range

Marijuana buds being cured in jars with Boveda Medium 62 Humidipaks

Now it’s time to enjoy the fruits of your labor!

Wouldn't you like to have your own jar of cannabis buds, too? CFLs can get you there!

Additional resources:

 

 

Jump to…

Complete Basics Guide: How to Grow Cannabis!

How To Get To Harvest As Fast As Possible

The Life of a Marijuana Plant (timeline)

How to Improve the Overall Quality of Your Bud

 

 

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