Cannabis indoors growers are an example of farmers who are always looking for an improvement that favors an increase in the quality of their crops. Thanks to this seek of an increased yield and quality; growers ask us how to upgrade specific parameters of their gardens.
This chapter will write about the characteristics, advantages, and disadvantages of growing in hydroponics systems compared to soil or coco fibers. We hope this information will be helpful for our readers and also for those growers who like to test other techniques.
cannabis growing in soil
Growing in soil is the oldest way of all methods used by men. Historically it’s been the most used method for its good results, simplicity. A grower can vary the soil in composition (altering its characteristics) to adapt it to his preferences during growth. So there are growers who like a softer ground (with increased coco fiber proportion), other ones who want to increase perlite proportion (improving the water retention and oxygenation), as other ones prefer to increase percentages of worm humus (known as a biological fertilizer that enriches soil life adding nutrients), or with bat guano (used to increase phosphorus and potassium reserves that will help both: root system and flower formation).
As major growers like to produce organic flowers, soil growing is one method that presents more interest (by being the only one that guarantees 100% satisfaction).
Growing cannabis plants in soil
When a grower wants to give his plants the best substrate possible, it is recommendable to know each strain and the needings. That’s why one plant in its early stages of growth will demand lower quantities of nutrients than a bigger one with higher needings. Referencing this point, it is recommended to use soft soils to favor a quick adaptation to its containers. Too-fertilized soil, or hard soil, may slow down plant growth and even cause overfertilization on them.
Transplants and growth
cannabis seeds usually need 4-5 weeks grow period before switching to the flowering phase. During this period, plants will show exponential growth (the more significant the plant is, the more it boosts) while they arrive at maturity (when plants are ready to start flowering). A very extended technique between growers worldwide is transplanting. This technique is usually used from the early stages during the growing phase until the plants are switched to the flowering phase. For example, we could use small size pots (half-liter) for the first 10-15 days, later on, transplant them to a bigger one (2 liters could be a great option) during the next growth phase for 10-15 days more). Once this time has passed ( and having a particular size), we could transplant again to its definitive pot with bigger capacity (indoors, the most used ones are those from 5 liters up to 7 liters). In the same way, we are increasing the pot’s size; it is recommendable to change to a more fertilized soil that feeds our bigger plants enough.
Following these steps, a grower can save fertilizing plants because every new pot is filled with fresh soil full of ready to uptake nutrients:
- It has more space to let the root system grow.
- Has fresh nutrients prepared to be eaten by plants.
At the moment, plants are switched of photoperiod to 12h/12h (to begin flowering stage), it is recommendable not to transplant more because they will stop developing its rots and won’t use much of the new soil given. Knowing this situation, experienced growers could use this process to keep shorter plants (plants will keep the same size for a few days as they are adapting to the new pot). Transplanting growers get more nutrients ready to feed their plants for a while, with a compact plant size compared to changing its pot days before switching to 12h/12h. The compact plant may help get more giant flowers due to a better incidence of light on them.
Substrat pH used for growing cannabis
cannabis soil usually has a balanced pH value close to 6,5. This value offers plants a total availability to absorb content nutrients. We like to remember that soil pH is fundamental for the evolution of young plants on it. A too acid pH value, or too basic, may slow down growth and even cause death. A high-quality substrate should guarantee a balanced mix that assures a stable pH during the first days (substrate pH may vary depending on the pH of the water used to feed the plants). Due to this pH fluctuation, it is essential to control the pH of the water used to provide plants. A mistaken pH value forces the plant to work on the process to transform this pH into an absorbable one, so plants will need more time to process everything given. Also, an unbalanced pH value may cause deficiencies derived from the incapacity of absorbing certain elements. At this point, we should notice that due to the plant’s needings during each stage may be recommendable to use a more acid pH value during the growing phase ( a pH close to 6 helps absorbing Nitrogen) and rise it slowly as the plants advance to the flowering stage (a pH value relative to 6,2-6,5 favors a better uptake of nutrients like phosphorus and potassium, two essential elements during flowering formation).
Growing cannabis in coco fiber
Coco fibers are an inert substrate and sight (it is common to use them to improve soil’s absorption capacity). As it is an inert substrate (there is no life on it), one of the main characteristics should be fertilized since the first feeding. Coco substrate is considered by most growers as something in-between soil and hydroponics because, as it happens in hydroponic systems, growers need to pay special attention to their plants, which need this care compared to a fertilized substrate. Techniques used, commented previously, are also valid in this media. PH values of the water used are usually lower than those used in soil due to coco’s pH value.
Growers like this substrate like it for its plant’s increased feeding control capacity compared to plants grown in soil. This extra control may be a benefit, in the right hands, thanks it offers to our garden only those nutrients that plants need in a particular stage.
Nutrients for growing cannabis in coco fiber
As coco is an inert substrate, the grower should add nutrients from the first day. Those nutrients could have a biological or chemical origin, depending on the likes of each grower and also on the method used to feed plants. While those manual feed growers could choose fertilizers and boosters, those who use a dripper system probably should choose the chemical ones. Some reasons justify the usage of this type of fertilizer:
- Chemical fertilizer could be prepared and stored for a while in a tank (that will feed the plants for the next days), something the biological fertilizer won’t be able to do due to its tendency to separate from water (after few hours, they tend to separate as oil and water do). Also, biological fertilizers are algae and pet friendly due to their composition.
- Biological fertilizers could present more difficulties to growers, which should maintain a daily look at the drippers (biological products tend to accumulate residues, and residues often collapse the dripper). This daily job must be done, or some plants could suffer a malfunctioning and die.
Another critical factor that usually affects growers in coco fiber is micro-nutrients (nutrients consumed in minor quantities than macro-nutrients, but with the same vital needings). Again, as coco is an inert substrate, there is no life on it, so there is a total deficiency of these elements on the substrate. Growers should ensure that fertilizers contain enough micro-nutrient and macro-nutrients to assure a nice evolution of plants. At this point, we like to notice that specific fertilizers for coco fiber growth usually are named as Two-part or A+B, where one of its parts contains macro-nutrients and the other micro-nutrients that should be combined (never directly, always mixing them in water) to get a nutrient solution rich on each one of the basic elements.
Flushing roots in coco fiber
Cleaning the root system is a key factor in growing cannabis to get high-quality flowers without traces of fertilizing products that could affect taste, flavors, and effectsThisis chapter is imperative when fertilizers are of chemical origin (the most used ones by growers on this media). Chemical fertilizers, with quicker uptake qualities, also have a longer duration in plants. That’s why it is so vital to establish flushing periods of the same, or longer, duration ( we recommend a minimum of 15 days to assure efficient flushing). There are products specially developed to make this process occurs faster. This kind of product could help coco growers (as well as hydroponic growers) to save some days flushing plants because they help to decomposition nutrients on substrate quicker.
Growing cannabis in hydroponic systems
In hydroponics systems, where plants grow, without any substrate, thanks to a constant flow of water. In these systems, evolution from volcano substrates where plants grow naturally in soil with water flowing is so fast, especially during the growing phase, because roots don’t have any resistance that slows their growth. In the same way that occurs with coco fiber, the hydroponic system’s substrate has no life. That’s why should exist a nutritional balance at every plant’s stage. As there aren’t any cushion media, it is important to maintain consistent quantities of water every day (and maybe twice a day) (known by E.C. or electroconductivity of water, expressed in PPM or mS/cm).
Hydroponic systems for growing cannabis.
Hydroponic systems are a resource used by growers worldwide. Its main benefit is faster growth, major sustainability (it doesn’t waste water because it’s in constant recirculation), and (in experienced hands) increases yield. These characteristics make hydroponics a commonly used system not only by cannabis growers but growing other plants under HPS lights.
Hydroponic systems are complex systems where, using a pump, the nutrients solution is constantly flushed to plants, from a water tank and then capturing all the undrunk water to the tank again. This constant circulation allows growers to increase, and also reduce, salt quantities almost every instant (guaranteeing total control over plant’s feeding). This control should be exhaustive, if not plant may suffer it showing lower crops and even a ruining yield.
Water quality: pH and EC
If water’s quality is important, working in other substrates, in a hydroponic system these parameters take an extremely relevant part. Plants will grow in this media and will take nutrients directly from it, so it is very important that water is of the best quality possible. For this reason, we consider it is fundamental to use water treatment filters (osmosis filters) so we get unsalted water to then add as many nutrients as needed. Osmosis filters are the only way to get water with low enough levels of nutrients (almost null, similar to distilled water). This water guarantees that, once the mix is prepared, it will only contain nutrients the grower has added (making it easy in cases of overfertilization or deficiencies).
Working with limited water it is recommendable to add 0,2 EC of Calcium and then 0,2 EC from Magnesium, before adding the rest of the nutrients in every stage:
- Recommended E.C. for plants on the first week of growing phase: E.C.= 0,6-0,7 uS/cm
- Recommended E.C. for plants on the second week of growing phase: E.C.= 0,7-0,8 uS/cm
- Recommended E.C. for plants on the third week of growing phase: E.C.= 0,8-1 uS/cm
Advantages growing in soil
The main advantages of growing cannabis in soil are:
- The easiest way to grow.
- It forgives possible errors from the grower
- Soil has nutrients on its mix directly uptaken by plants
- 100% organic grow (using BIO fertilizers)
- Is the cheapest way to start growing indoors
Disadvantages growing in soil
The main disadvantages of growing cannabis in soil are:
- A lot of water is wasted (containing expensive nutrients)
- More dirty growing spaces (do to substrate movement)
- Less control over plant’s exact feeding
Advantages growing in coco fiber
The main advantages of growing cannabis in coco fiber are:
- Increased control over plant’s feeding
- Plants uptake more nutrient solution
- Quicker grow (lighter substrate)
Disadvantages growing in coco fiber
The main disadvantages growing cannabis in coco fiber are:
- Inerte substrate(more difficult for beginner growers)
- Recommendable to use chemical fertilizers and boosters (biological offer more problems)
- Requires more attention by grower (and more knowledge)
Advantages growing in hydroponic systems
The main advantages of growing cannabis in hydroponic systems are:
- Faster growth
- More abundant flowering
- More efficient water consumption
- The system has more autonomy
- Cleaner system
- Possible to re-use the substrate
Disadvantages growing in hydroponic systems
The main disadvantages of growing cannabis in hydroponic systems are:
- A daily must control of plant’s water parameters (E.C. and pH values)
- Major technification of growing room (water pumps, timers …)
- Totally chemical system media
- Water temperature should always be 21ºC (upper and lower may cause problems)
- Facility for pests to conquer substrate and ruin the crop
- Plant’s size (bigger plants need screens or tips to hold ‘em due to a no-substrate.
Conclusions about type to substrate to use growing cannabis indoors
As we are knowers of the different substrates were to grow cannabis, being grown in all of them many times, our experience tells us that every grower has its substrate. Those lazy growers or the ones that prefer not to become a slave from their garden should grow cannabis in soil. All those who like the benefits of hydroponics, but do not have experience or budget, should try growing cannabis in coco fiber. For last but not least, growers who have all the time in the world, the necessary budget, and like to quicker changes on their plants, should try hydroponics.
If we talk about quality, our tip is to grow cannabis in soil, because this substrate gives plants a taste, odor, and quality incomparable to other substrates.
If we are looking for a good relation between easy to grow and yields per crop, we especially recommend growing cannabis in coco fiber.
If what is important in our crop is the volume and weight of our harvest, it makes sense to apply an extra effort and grow cannabis in hydroponic systems