Soil vs. Hydroponics for growing medical marijuana? A hydroponics store won’t tell you.

Indoor hydroponic portable grow unit

So in this industry have you ever tried to walk into a hydroponic store and asked what is better for growing medical marijuana, soil or hydroponics?

What will happen next is shocking but they will either ask you to leave or tell you to don’t talk about it in their store. I mean 95% of the customers that walk into their store are growing medical marijuana, yet they cannot educate you on the different products they sell and give you advice on which media is better to grow medical marijuana in at your experience level, novice or advanced? To me this is one of the most hypocritical things I have ever experienced, and I believe people should know things like this in order to produce better quality medicine and know how to use the products that are being sold in these stores. The funniest thing is the experts at these stores are probably growing medical marijuana themselves. You shouldn’t feel like you have to consult books, or take classes, or scour the internet instead of asking an expert at your local hydroponic store of what these products actually do. So I am here to shed some light on this argument that every hydroponic store will not tell you about their products because you’re growing medical marijuana, NOT tomatoes.

In the growing scene, there are so many growers that will argue which media is better to grow in, soil or hydroponics. There is a big misconception to this argument that can be remedied through the science of growing, and how the plant is actually grown. Truthfully, both ways of growing have their pros and cons. It really all depends on what you’re trying to achieve in the growing process. There are some basics though. One of those basics is the more you can feed your plants accurately whether it be nutrients or C02, the faster it will grow and the bigger the yields.  Also remember that these are only some influential variable factors and good genetics are the base key to a healthy harvest.

Let’s start with soil. Of course soil is considered the “organic” way of growing, especially when you amend the soil and just use PH balanced water to feed it, naturally breaking down the organic substances to feed the plant. The process begins underneath the soil when the water saturates the medium, causing reactions between the enzymes, organic elements, and bacteria that are naturally present. This process takes awhile, but eventually feeds the plant giving it the vital nutrients that it needs. The soil acts as a buffer zone which is the most forgiving medium, and the plants can sustain for days without more water before they start to dehydrate. This makes soils a very good first pick for novice growers.  The soil also has humates, an organic substance that helps with the final taste of your buds. Soil based media however can also carry diseases, pests, and other forms of unhealthy things with it if your not careful of where you actually get it. If you try to feed to much it can waterlog, causing your plants to yellow and wilt. You can add perlite to get better drainage and feed more, but your plant suffers by taking out the vital nutrient components in the soil thats being replaced by the perlite. Also, if you amend your soil with multiple organic elements like bat guano, blood meal, kelp meal, etc., you cannot accurately control your nutrients during different stages of the plants development, making it much harder to direct the outcome. What if you use organic nutrients on top of all that? Even though the ratios of your nutrients you are feeding may be right, you always have to take in account what is already in the soil, which is extremely difficult to do and could end up hurting more than helping.  Soil can also be very messy to plant and its hard to haul out everything into the organic vegetable garden out back, if you can even make one. You can still produce a good harvest with soil, but it doesn’t always give you that extra punch because you just can’t feed your plants fast enough in the given harvest time.


-        Most forgiving medium and soil acts as a buffer zone

-        Can be the truly “organic” way of growing and has humates

-        Does produce very well in some instances

-        Makes a good first pick for novice growers


-        Can only feed so much, and can only have so much drainage

-        Can carry pests, diseases, and mold

-        Can’t effectively regulate nutrients to shape outcome

Hydroponics is a popular method of indoor growing for several reasons. There are many different types of hydroponic media and systems available on the market today for you to choose. One of the reasons why it is so popular is because it does produce consistent heavy yields when done properly. Why?

Well let’s look at the first steps of it, the medium used. Let’s say we want to try and stay a little bit organic and use a hydroponic soil-less medium like Coco-Coir. Coco-Coir is a coconut husk that is cured and dried. It has a nearly perfect PH right out of the bag. It does have some issues with binding calcium and magnesium, so having a cal-mag solution is good to use with it eventually if you start to see deficiencies. We are using this in a grow tray with what is called a “drain-to-waste” system, which means when the plants are fed they are fed with very little runoff, much like soil. You automate the system with timed irrigation, so you have a large reservoir you mix your nutrients in and as the marijuana plants gets bigger, you feed them more frequently. Coco doesn’t retain as much water as soil, and ends up drying out a lot faster.

There are no amendments in the soil, and all the nutrients come from the mixture. So not only can you feed them exactly what they need, but you can adjust the nutrients to the appropriate levels and add whatever you need at certain stages of the plants growth. Like towards the end of flowering, you can add a phosphorus booster to make the buds swell harder without burning the plant because there were no extra things in the medium to calculate other than what your feeding it. Since we are using Coco, the plants get much bigger because not only are the plants getting what they need, we are not overdosing them with spikes of different nutrients that are not regulated.

However if we provide it with a low parts per million, we could start seeing deficiencies that are hard to diagnose. Not only that but we have to make sure that we flush the plants on at least a bi-weekly basis because there could be a salt buildup which also causes deficiencies.  Algae could start growing if we don’t cover the tops of containers, and an overdose can likely happen if we are not careful with the mixture.

The rewards of growing hydroponically can outweigh soil just for the shear fact that you can feed the plant more often with fresh nutrients. As long as all other factors are in place such as lighting, aeration, and tending, the plant will grow faster and bigger, cutting down vegetative times and producing larger harvests. Using a well balanced nutrient program, and caring for your plants well, will give you a greater yield when using hydroponics. The plants must be flush thoroughly in the end, or your buds will have a harsh taste and make you cough.


-        Can feed plants more often making them grow vigorously

-        Nutrients can be regulated properly increasing yield

-        Multiple systems that increases growing efficiently

-        Can achieve larger yields easier than soil


-        Can easily overdose or underdose

-        Salt buldup is common in hydroponics

-        Some systems can break down easily and need to be maintained and stay clean

-        Algae has a tendency to form on hydroponic media

So it all depends on how you like to grow and what you want to do. Each way has its pros and cons on what will happen in the end. The factors always are taste, effect, yield, appearance, and aroma. Some will do better than others, but it is always nice to have too much than not enough!