Growing Tips

How To Grow Marijuana/Cannabis

First in a series on how to grow Marijuana


The word, “Hydroponics” means “water working,” and it is a known method of growing cannabis. The process of growing cannabis with hydroponics means growing plants in either a flow of oxygenated water filled with nutrients or a bath of water. Hydroponic method of growing cannabis means that you are growing the plant in another growing medium apart from the soil. You supply all the nutrients that the plant needs in the water. Growing cannabis hydroponically involves the introduction of nutrients, water, and air to the roots of the plants through a growing medium since hydroponics does not involve roots and the energy required for soil growth; thus, hydroponics produces fast-growing cannabis plants.

Plants have a water content of 80% to 95% and the remaining parts comprise of oxygen, hydrogen, and carbon. These elements are extracted from water and air by the plant; thus, nutrients make up only a tiny percentage of what a plant weigh. The hydroponic environment helps control the entire plants’ environment so that you can reap the perfect cannabis yield.


Marijuana plants and as a matter of fact, all plants do not have to be planted in soil for them to grow. The only things that a plant needs to survive are nitrogen (N), magnesium (Mg), phosphorus (P), calcium (Ca), sulfur (S) and potassium (K). These are the major elements known as macro-elements while the small elements include iron (Fe), manganese (Mn), copper (Cu), chlorine (Cl), zinc (Zn) and boron (B). Using hydroponics to grow marijuana involves putting all of these nutrients inside water to create a perfectly balanced nutrient solution. A nutrient solution that contains a blend of secondary elements such as magnesium, sulfur, and calcium with trace elements such as copper, boron, iron, molybdenum, manganese, and zinc will help make sure your cannabis plant gets through all stages of growth. You can adjust the levels of nutrients that your plant needs at different stages of growth. For instance, a 15-15-15 solution is made up of 15% Nitrogen, 15% Phosphorus and 15% Potassium. A 20-10-15 solutions contains those numbers in percentages for each of the constituent elements, NPK. When you are buying hydroponic nutrients, go for powdery nutrients that you will have to mix with water instead of the premixed solutions.

What is the importance of NPK in nutrients?

N, which stands for Nitrogen is responsible for ensuring healthy foliage in your plants.

P, which stands for Phosphorus helps ensure strong roots and;

K, which is Potassium helps ensure a hearty growth.

  • Nitrogen is needed in high amounts during the times when the temperature drops less than 80 degrees in your grow room when the cannabis is in the vegetative growth. A nutrient mix in the proportion of 20-20-20 or 12-6-6 should work effectively.
  • If the temperature goes beyond 8- degrees, you do not have to worry about Nitrogen during vegetative growth.
  • At the flowering stage, your cannabis plant needs a lot of Phosphorus regardless of what the temperature is.
  • Keep the fertilizer at a minimal level so that you will not kill your cannabis plant. If you are scared of not using enough fertilizer, your plant will not die; it will only take time to grow. Follow the mixing instructions as listed on the solution package. If you do not know the right amount to use, it is better to use less than use too much.
  • Plants absorb water from evaporation, and this is why you have to regularly top up the water because the level of water in your reservoir will drop.
  • Change the nutrient solution regularly with an interval of two weeks in between. Throw out the old solution and clean the entire reservoir and pump.

Nutrient Cycle for a Marijuana Plant

When the pump starts working, your plants’ roots should get submerged under the water every twenty minutes, and once this happens, the pump can go off. Of your roots do not get water for more than 20 minutes, the roots will grow longer as a result of their search for the source of nutrients and trying to reach the nutrient source. If they grow too long, it may become difficult or impossible for the solution to reach the grow cups.

This could also lead to the root material getting ripped out and clogging the water flow system, and this gives you more work to do because when that happens, you will have to dismantle the entire garden to clean the clogged parts.

Check the length of the root from time to time. Make sure the root is short enough not to touch the narrow point where the solution stays in the cup holder. The roots should never be anchored to the internal channel. If the roots are too long, trim them a little with a pair of scissors and ensure they do not reach too far but don’t just cut because you feel like it.


You should never confuse supplements with nutrients. If the NPK ratio in a particular nutrient is 0.3-0.3-0.1, what this means is that the product is not a base nutrient but a supplement. If you give your plant the right amounts of micronutrients and NPK by using base nutrients, your plant already has all it needs to grow. Supplements are good, but if you give your cannabis plant too much, it could lead to adverse effects on the plant or even burn up the plant. Just play safe if it is your first cannabis grow. Use base nutrients and supplements produced by the same company to reduce negative reactions. But generally, try and reduce the supplements you use on your plants because most times, your plant does not need them.


Getting into the business of growing cannabis is serious business, and you want to do your best to ensure that your plants are fed with just enough nutrients that they need to grow. Follow the tips and information stated above, and you should do just fine.