Indoor Marijuana Growing In Soil

Indoor marijuana growers face a unique dilemma when deciding how to grow their crop: should they grow in soil or in a hydroponics system? If you haven’t before considered a hydroponics system and you have a larger budget, you may want to look into it.

Many growers opt for soil when they are starting out. This is a good way to get to know the plant and how it functions, without over-investing in the process. You can grow a fully biological product, and you get to take advantage of all the agricultural knowledge humans have accumulated over the last several thousand years. Pretty neat, right?

Whichever method you choose, you should do the proper amount of research to ensure that your harvest is successful. This article covers the pros and cons of growing marijuana on soil.null

grow marijuana in soil

Advantages and disadvantages


It’s easier to irrigate plants in soil, or more forgiving at least. You don’t need to be quite as careful as you do when watering plants in hydroponics systems. Plus, the fertilization is easier to deal with in soil. It’s conventional, and so you can draw on a huge knowledge base. If you’re having issues, you’ll be able to troubleshoot them reliably. Different soils can also impart enjoyable and unique flavors to your harvest, which can frequently be a huge plus (although not necessarily).

Download my free marijuana grow guide at this link for more growing tips!

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    Unfortunately, dirt is heavy, and it takes up a lot of space. This is a problem for a lot of indoor growers who only have limited space. Plus, dirt is, well, dirty. Your chances of getting insects or pests goes up substantially when you use a soil substrate for your Cannabis plants.

    The factare, some people just aren’t gardeners. There’s a certain sensibility that goes into planting seeds in soil and coaxing the up into beautiful towering plants. If soil isn’t working for you, consider the finely tuned science of hydroponics systems.
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    Size of the containers

    Marijuana Container

    The size of your Cannabis plant will correlate directly to the size of its root system. This means that the more space your plant has to expand its roots, the more easily it will grow. If the Cannabis plant ends up being too large for the pot, you will run into issues with nutrient and water absorption. Your plant will have a minimized efficiency, and the soil will likely burn through water quickly.

    Cheap cannabis seeds are never part of our inventory. Instead, check out these great deals on the best quality feminized marijuana seeds.

    Seeds Deals

    In general, if you have an average Cannabis cutting or seedling, a pot with dimensions of roughly 10x10x10 cm will be large enough for you. If the plant has reached the height of 25-35 cm (especially if it hasn’t stopped growing), you’ll need a pot that’s roughly twice as large, around 15x15x20 cm. If your plant grows larger than 80 cm, you’re going to need a pot that holds at least 10-12 liters. Once the plants reach any size larger than a meter, the size of the pot increases accordingly.

    Repot the plant when necessary (and carefully) as it matures.  Remember to keep an eye on the plant as it grows. If your plant never has room to get bigger, it never will. Check this link for the best pots to grow marijuana.
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    Unfortunately, all of these natural processes can be difficult to duplicate for indoor growers. The best bet is to start out with nutrient rich soil and to make sure the soil has been sterilized before you begin potting your plants. Sterilizing your soil with heat won’t guarantee that you’ve killed every possible parasite and disease, but it’s an important preventative step. All it takes is one nasty parasite to spread around and ruin your entire crop.

    You can purchase a potting soil mix at a garden shop or mix your own. In either case, you’ll want to create an environment with plenty of oxygen, a temperature around ~20 degrees C, adequate water (moist but not wet), a pH value of 5.8-6.5, and plenty of nutrients. Read the article “Measure pH and TDS of your soil” and learn how to measure the pH and TDS of your soil.

    If you’re growing indoors, be careful to meet all the requirements of the soil. The acidity, humidity, and nutrients available in an environment will determine a great deal when it comes to your plants success. A proper pH value in your soil will maximize the absorption of nutrients. You can use chalk and Epsom salts to change the pH of your soil. Or you can buy pH-up and pH down at this link here.

    Water retention is also very important in your soil: if your soil drains water without retaining it, your plant will get thirsty fast. If there’s too much water, fungus could grow in the soil and damage the roots. Consider modifying your soil with vermiculite, sphagnum moss, turf, or perlite if you want to change how your soil retains and drains water.

    Learn how to harvest marijuana and protect your marijuana plants

    Harvest Guide

    • Time your harvest for Perfect Taste
    • Get THC levels for a Perfect High
    • Don’t waste any Precious Bud

      You’ll also want to make sure you have the right amount of nutrients. Lots of nitrogen, a moderate amount of potassium and phosphor.
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      Cannabis soil

      If your pH is rising too high, you can add some chalk to bring it back down. Also, you can easily add liquid fertilizers into your plant when to water. If you plan to make your own liquid fertilizer, make sure you have it mixed well. If the mixture isn’t well-balanced and homogenous, your plant will absorb nutrients unevenly and could experience a nutrient burn. If you don’t feel comfortable with the idea of making your own nutrient mix, there are a number of mixes available which are specifically for the cultivation of marijuana. Read more about soil in the article “Marijuana Soil
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      In general, water enough so that your soil is faintly moist, but not wet. If the soil is too wet, you risk fungal growth and root damage.

      Faq about indoor marijuana

      What are the best autoflowering strains to grow indoors?

      Here is our list of top picks for indoor growing: Super Skunk Automatic, White Widow Automatic, Sour Diesel Auto, Super Silver Haze Autoflowering, and Northern Lights Automatic.

      What are the best feminized strains to grow indoors?

      Here is our list of top 5 fem strains to grow indoors: Blue Dream, Big Bud, THC Bomb, Chocolope, and LSD

      What are the best indoor strains for yield and potency?

      There are many strains that can produce high yields with great potency, here are some examples: Big Bud, Power Plant, Super Silver Haze, and Green Crack

      Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible


      Robert Bergman

      Robert Bergman is an Amsterdam-based marijuana grow expert who has years of experience from small grows to massive operations. His passion for growing lead him to develop his own Gold Leaf strain. Now, Robert is dedicated to sharing his knowledge with the world.... [Read full bio]


      marijuana grow bible
      • Grow With My Quick Start Guide
      • Discover Secrets To Big Yields
      • Avoid Common Grow Mistakes

        41 comments on “Indoor Marijuana Growing In Soil”

        1. I use a mixture or vermiculite, seed raising mix and organic potting mix. I use self watering pots, that have a 1 inch gap between the bottom of the pot and the soil mix and has an opening to drain excess liquid.and I, personally, drain this everyday. These pots also make it much easier to flush your plant before harvest. The pot is mostly filled with organic potting mix and vermiculite mixture and in the centre and to a certain depth a mixture of seed raising mix and vermiculite, this is where I plant my seeds. It’s a great system, I swear by it!

        2. We want to transplant a small plant into a 10 gallon grow pot. we bought chicken. worm castings, Hydrolyzed fish fertilizer, 2-4-0. we want to mix it up in the pro mix and then transplant. is this enough for npk

        3. Hi, I’m trying to set up auto-watering for a small indoor soil situation.
          I had a constant drip feed for a portion of the last crop and it didn’t seem to love it. After researching, I read about the ‘root cycle’ whereby the roots like to alternate between being watered and access to dryness/atmospheric oxygen.

        4. I just thought about, what if you get the nutrients packs off roses when u buy roses and then when you go to water your weed soil u mix the flower nutrients in the water and then water ur weed soil?

        5. I am just getting set up for an inside grow, i have a 4/2 by 5 tent 1200 wat full spect led and have wite widow auto seeds germinating now when ready my plan is to plant them directly into 5 gallon pots any help or sugesti would Be greatly appreciated As i said i am very new to this and am only going on research i can find

        6. Carol, You should join our forum so that you can get strong grow advice from our many expert and friendly growers. 🙂

        7. Its been 4 weeks since I planted 6 seeds and all 6 have been doing great now Two of them the bottom leaves are curling what do I do

        8. I started growing inside this last year 2018 after growing outside for42 years. I have read many articles on what dirt to use but nobody has ever given a good answer. I read many articles starring run from miraclegrow potting soil so me as a non believer in What most folks say, I started growing in these potting soil. I have harvested 9 different plants and on average I get 1.5 oz to 2.5 oz. I don’t know about ph levels and things like that but I believe I get good results.

        9. Gary Baier,

          A hot soil like FoxFarm will contain the necessary nutrition to get you through the vegetative cycle for the most part. You need to watch your plants in order to make sure they retain a nice green color. In general we recommend that you refrain from adding nutrients in a Foxfarm soil grow until the flowering phase. This is because the FF soil has enough nutrition for 4-8 weeks depending on environment, lamp intensity and how aggressively the genetics are.

          Happy growing 🙂

        10. Can I use any nutrients thruout my grow even if my babies r in fox farms ocean forest if so at what point should I start

        11. Linfa,

          First let me say I am sorry you have Lupas. I have a close friend afflicted also.

          Cull the seedy plant if you are sure the other is a female. If one is flowering and the other is not; You may have a male and a female with seeds. I suggest you buy feminized seeds from here on out to make sure you get you medicine and I also think you should join us at and allow us to help guide you to a successful harvest.

          Pollen sacks open and produce little flowers when the pollen is spread. If the plant has seeds on it, the the plant is a female that has been pollinated or a hermaphrodire plant that produces male and female flowers. Without pictures, it is hard to tell what the pretty green without flower…is?

          Hope this helps. We would like to see you grow successfully. 🙂

        12. I’m first timer,indoor grower ,started with 4 plants ended with 2 ,both are about 3 is tall with alo t of small white flowers and seeds the other is a beautiful green plant that I love,what can I do with seedy plant.? Is it any good ? I am a Lupus patient .

        13. Thanks, Robert. My first grow wasn’t a huge success in quantity (harvested about half of what I should’ve) but it was quality &what I gained in experience & knowledge will be irreplaceable in keeping my everyday nerve pain in check. Thank you so much for helping me get back some quality of life. You truly are making the world a better place.

        14. Going to try my hand at an indoor grow using White Widow Auto. Can I Scrog or use LST to increase yields? Or should I just let it grow on its merry way?


        16. […] Sour Diesel takes a little longer to flower than other strains but it is well worth the wait. An indoor-grown plant can yield up to an estimated 18 ounces per m2 on average per […]

        17. where do you get the light my windows are kind of high and no ledge how much light do they need do you buy special bulbs ?

        18. Hi Darcy, I admit there are more than one way to grow our beloved plants. Maybe you could hop onto our support forum. Our experts there are happy to help you as are fellow growers.

        19. I’m so confused. I don’t even know where to start. First I THINK I downloaded your Bible. I received at least 3 messages from Robert. I see so much information and also see ADS for this Bible to download. I thought I DID that already. I DON’T KNOW.
          I have some seeds started indoors .Some are labeled with date planted and strain type also have some notes as to which soils I tried. I see itty bitty BUGS. They don’t seem to be eating the plants. Some plants are flowering. I tried trimming just 2 plants ONCE . It seemed to work and spread out a little but I am too scared to try it again. A couple plants just keeled over and died while others are hanging in there. I am also experimenting with different types of containers. I probably should have just followed YOUR step by step instructions but I think it might take me a week just to research your choice vocabulary in said articles. Like I said before I am confused and your emails are long and maybe too informative I Don’t know. Maybe I need a marijuana growers FOR DUMMIES.

        20. Thank you for the lesson .i would like to know the temperature for indoor growing ?

        21. Flintz,

          Of course plants stop growing at the end of their life cycle. Is this a trick question? LOL 🙂

          I suggest you join our support forum in order to expose yourself to many knowledgeable growers and experts willing to help you succeed. 🙂

        22. I’ve got two flowered plants and it seems that they have slowed in growing does this happen at the end of the life term of the plant?

        23. Hi Flint, Thank you so much for sharing. We are really happy to be of any help. Let us know if you have any questions.

        24. Robert,
          Thank you for all your help, since you’ve been sending me advise I’ve went from someone that wasn’t sure that I
          wanted to grow but didn’t think I could, to someone that is a little more comfortable with what I’m doing.
          I am in my fourth grow and I feel very confident that I will soon be at the end of another successful grow.
          I want to stop growing from street seeds and start with some real good Strawberry cough, Blueberry kush, and some Black and White widow.
          After this harvest, I’ll be sending you a money order or cashiers check for the afore mentioned seeds!
          Thanks again,

        25. Rabbit droppings make for excellent soil when starting. Rabbit droppings cannot burn your plants regardless of how much you use. After planting seedlings however I suggest a good nutrient based diet for the growing phase used once and week, then for the flowering phase used 3 times a week.

        26. Have you done a search on the viability of using Rabbit manure on vegetables? That would be a good place to start.

          Another option would be to join the ILGM Support forum and ask the many members; Many of who grow vegetables, organically, and may have some insight to contribute to your query

        27. I keep a rabbit pen on the side of my house, and was curious about using their droppings in my soil for added nutrients. They have been raised on a diet of Timothy hay, sunflower seeds, pumpkin seeds, carrot, banana, papaya and the occasional fresh watermelon or cantaloupe. Would this be an ok additive?