Marijuana can be grown for either harvesting THC or CBD rich trichomes or for breeding. Whichever your intention, it is important to understand that you can only grow healthy plants when all nutritional requirements are met. In order to flourish and reach maturity, cannabis plant requires certain nutrients just like any other plant. These nutrients work with the plant to help facilitate photosynthesis, sugar production, cell growth, as well as many other biological functions of the plant. Your plants will react to any deficiency in their nutritional uptake.
In most cases, the signs of mineral deficiency begin to manifest in the form of discoloration. The leaves may turn pale yellow or dark brown in more severe conditions. The discoloration mainly occurs on the surface of the leaves, but may also occur along the edges. When marijuana plants are deprived of enough nutrients, they suffer from slowed growth and are prone to pests and diseases. In addition, it results in poor yields.
It is important for all marijuana growers to be well aware on the various nutritional requirements for the cannabis plant at different stages of its life cycle. Here, you will get detailed information about the nutritional requirements of cannabis plant, and how each of these elements contributes to healthy growth.
Understanding the Nutrients
Choosing the right marijuana fertilizer is a crucial decision. It involves understanding the main uses of various nutrients for your cannabis plant, and how to identify the signs of nutrition deficiency early. There are many types of fertilizer containing various forms of elements and minerals. Fertilizer may come in the form of a powder, granular, or liquid. They are almost always well concentrated and will need to be diluted with water before any application.
Cannabis plants thrive when they are fed with sufficient amounts of Nitrogen, Phosphorus, and Potassium (usually specified in nutrient products in the format NPK). Even so, additional micro-nutrients are also required in small traces to help marijuana strains to grow to full strength. These micro-nutrients include calcium, Sulfur, Magnesium, Molybdenum, Boron, Copper, Manganese, Zinc, and Iron.
Nitrogen is the major component of amino acids which are used in all growth processes. Amino acids are used in plant cells as building blocks for protein, the green chlorophyll pigment, and enzymes. Chlorophyll is essential to plant growth because it plays the role of converting energy from light into an energy for the plant (in the form of sugars and carbohydrates).
- Nitrogen deficiency can be characterized by:
- Purplish tints on the underside of leaves and on the stem
- Stunted growth (slow growth)
- Older leaves turn yellow
Phosphorus is responsible for transfer and storage of energy within a cannabis plant. It can be described in simple terms as the
power station required by a plant to accumulate and consume energy from photosynthesis. Phosphorus is also a component of DNA, proteins and many enzymes. It is associated with seed and resin production.
The signs of insufficient supply of Phosphorus include:
- Stunted growth (slow growth)
- Older leaves curl downwards and turn into dark colors
- The stems of leaves turn purple or reddish
- Smaller leaves with blotchy spots
The marijuana plant requires potassium for several critical processes which include uptake of water, development of cell walls, and flowering. It keeps water and other nutrients moving freely around the plant. Potassium also helps the cannabis plant to resist, environmental stress, pests, and diseases. Potassium is an essential component used in the manufacture of sugars, and cellular division.
Inadequate supply of Potassium can be characterized by:
- Leaf edges appear burned and the tips curl up
- Stems become weak and brittle
- Older leaves begin to turn dull, yellow, and eventually, develop rusty spots
To ensure that your cannabis plant achieves an overall healthy mix, you should also consider additional nutrients. Most of these
nutrients are required in trace amounts.
Magnesium (Mg): it is contained in chlorophyll and is essential to absorption of light energy. It also helps nutrilize soil acids and toxic compounds. Magnesium intake usually increases during the flowering stage of Cannabis.
Calcium (Ca): it is responsible for building healthy root structures, strong growing points, and cell walls. Additional calcium is required during the flowering phase of cannabis
Sulfur (S): it is used in the formation of amino acids, vitamins, and proteins required for chlorophyll production. It is essential to the creation and breakdown of fatty acids, as well as respiration
Molybdenum (Mo): this nutrient is almost never deficient. It helps convert nitrate to ammonium.
Copper (Cu): this is required in production of enzymes that aid plant respiration. Copper can also be used as a fungicide.
Boron (B): it moves sugars around the plant. It is also involved in calcium uptake. Boron deficiencies don’t usualy occur when growing indoors
Manganese (Mn): is crucial in activating enzymes that work with photosyntesis. it is involved in germination, growth, and the production of new tissue
Zinc (Zn): works with other micronutrients like manganese and magnesium to help form chlorophyl. It is is associated with protein synthesis and chlorophyll production
Iron (Fe): helps carry oxygen and light energy around the plant and it is also involved in chlorophyll production
When Does Your Marijuana Plant Require Nutrients?
There are several factors that determine when to use these nutrients. For example, the type of soil used and the particular stage of
growth that the cannabis plant has reached are critical in choosing the right cannabis fertilizer.
In the early stages, the marijuana seedling doesn’t require many additional nutrients. Canabis sprouts usually obtain enough nutrients from a good soil mix. Additives like mychorrizae and humates may be added to help promote strong root growth. Some will water seeds in a very diluted fertilizer mix to speed up germination. While germinating seeds require darkness and warmth, sprouted seedling require a lower light intensity for 18 hours a day and a moist not waterlogged soil. Vegetating
and flowering cannabis plants typically requires much larger amounts of nutrients and a stronger ight source.
During vegetative stage, leaf and stem development are are attempting to work at full speed. A vegetative marijuana plant will require a nutrient solution with high nitrogen and low phosphorus. Nitrogen helps the overal growth of the plant and will be required in high amounts during this phase of growth. As the plant grows it will require an ample supply of introduced nutrients (on top of Nitrogen) to maintain its quick growth rate.
The recommended ratio of NPK for a vegetating fertilizer is N10 – P10 – K5
In this stage, the cannabis plant requires a nutrient mix of high phosphorus and low nitrogen. Phosphorus and magnesium help the buds to swell which in turn maximizes the yield. Since the plant is now focused on flower and seed production, Nitrogen takes a back seat compared to the other required nutrients.
The recommended NPK ratio needed for flowering plants is N5 – P25 – K9
It is important to understand that the nutritional requirements may vary depending on the type of marijuana plant grown. Therefore,
the ideal nutrients must be determined through experimentation. Because marijuana nutrients and fertilizers play an integral part in the growth cycle, you should ensure that you use them correctly to avoid deficiencies and toxification of the soil.