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The Essential Nutrients for Growing Cannabis


Growing amazing weed takes some skill and some talent.

It can take cultivators years to learn how to grow great weed. The high cost of entry to the cannabis market and steep learning curve naturally prune all but the most dedicated horticulturists. Pests, expensive equipment and grower error account for most of the steep and long learning curve to greatness.

Nothing hurts quite as bad as realizing that a whole crop just died because you messed up the nutrient mix in the hydroponic system. Mistakes happen but it can take a long time to learn all the ways things could go wrong. Avoiding problems is especially difficult if a grower doesn't have formal training in biology or biochemistry.

In addition to having to invest hundreds or thousands of dollars in startup costs, it takes time to harvest and cure each generation of weed. Most small cultivators harvest once every three to four months while the big boys have enough space to set up continuous harvesting cycles so something is always getting turned out.

Crops are always at risk.

There is always a chance of losing a crop until it's sold. You can do perfectly throughout the grow process but if the cure is off, it can destroy the effort. Mold, mildew and pests can make even the best looking bud unsellable if left unchecked. Worse, they can make weed dangerous to consume if unscrupulous stoners get their hands on it.

In a growing number of states medical and even recreational cannabis cultivation is legal. These states have begun licensing retailers and cultivators. Those licenses cost money to obtain but then there are testing and packaging fees. If you don't have the starting capital to absorb these costs, you might just be risking a lot more than you think.

More and more small producers are getting drowned in paperwork and mounting costs. The cities and states that have legalized sales continue to add costs and regulations. The challenges these additional fees and other restrictions create actively make growing more expensive. The inflating price of entry makes having strong genetics more important than ever before.

Genetics play an integral part in cannabis cultivation.

The difference between sativa, indica, hybrid and high CBD strains comes down to genetics. Genes also play an important role in the height and yield of a cannabis plant. By breeding plants with different genetic traits, breeders can develop specialized strains that create a specific high or grow in specific ways.

Durban Poison, Sour Diesel and many other sativa dominant strains tend to grow very tall (5+ feet indoors) during their flowering cycle. While Blueberry, Grand Daddy Purple and other indica dominant strains tend to grow short ( 2-4 feet indoors). There are also other differences that breeders have developed over the last few thousand years which lead to the massive number of strains available today.

Whether they know it or not, cultivators and breeders have manipulated cannabis on the genetic level. Modern producers understand how to get the exact traits they want. The process goes back thousands of years and is called selective breeding.

Successful breeders understand the power of genetics. 

As Mendel discovered with peas in 1865, there are three types of genes. We call them dominant, recessive and shared. If one plant has a dominant gene and the other has the recessive gene, the dominant gene always shows up. Mixed genes find a balance between the two starting genes and both show up.

Dominant and submissive genes govern things in cannabis like Height and disease resistance. While mixed genes govern things like height and terpene profile. There is a lot of redundancy and overlap with genes which results in many different genes governing any given process.

There is a random element mixed in so it may take many tries to find the exact traits a breeder is looking for. Growing multiple plants at once will reduce the overall time needed to create the desired phenotype but increases the overall cost to start and maintain significantly. In addition to the genetic components, there is the very real environmental contribution.

So the best bet is to grow the best weed possible.

Just like humans, plants need to have high quality nutrients, plenty of light, clean water and lots of air in order to thrive. If they don't get what they need, they simply won't perform well. They may live, but they won't be amazing weed.

In a mistreated plant the THC or CBD levels might be low. The flowers/colas might be light and airy or the plant might just not produce much of anything. Finding the cause and eliminating it in time to save a crop is what separates bad growers from good ones.

The added effort and care can mean selling a pound of pot for $4000 compared to $1200. That adds up when commercial medical and recreational growers are harvesting over 100 pounds at a time. Especially when you can sell it throughout the state without risking jail time or the black market. So there is a huge incentive to providing the best conditions for the plant to grow.

Nutrient systems help eliminate errors.

Without getting too deep into genetics and biochemistry, nutrient systems are like performance food for plants. And cannabis has a very special diet that involves three staples; nitrogen, phosphorus and potassium. They need different amounts of these three chemicals at different points in the life cycle and getting the balance just right is really important.

Commercial options like Advanced Nutrients, Vegamatrix and Dakine 420 offer a pretested schedule to follow with exact amounts of additives needed. Most systems are divided into three parts and there are certain points in the growing process where more than one part is used at a time. As cultivators get accustomed to a specific nutrient line or strain, they often need to make adjustments on the fly to keep the system in perfect balance.

Advanced cultivators may also try to create their own mixes with exotic ingredients. Substances like molasses, bat guano and seaweed seem like odd things to add to soil but they provide some of the micronutrients that coco and rockwool simply don't have. But these exotic additives can also harbor pests and disease if not properly handled so don't go harvesting poop from your nearby caves without some serious research.

Cannabis grows in three main stages.

Baby cannabis is known as seedlings and clones once the seed pops open or a cutting is taken respectively. At this point the plant is very sensitive and it can die under intense light. Humid growing domes are often used in this stage to keep the plants hydrated as they establish an early root system.

Once the plant begins producing real leaves it enters the vegetative state. Unless it's an auto-flowering strain, the plant can stay in this stage indefinitely. Plants that are kept in this stage to produce cuttings or clones are called mothers and usually live for many years. The biggest reason to keep a mother instead of growing from seed every time is that the clipping is genetically identical to the plant it's clipped from.

When a plant is ready to produce weed it goes into flower. During this stage the sexual characteristics become visible for the first time. Female plants grow flowers and develop sticky trichomes full of cannabinoids like THC and CBD. Male plants develop pollen sacks and cause females to produce seeds so are normally culled once identified.

Make sure to mix in the right order.

Most cultivators have to add nutrients to the grow medium. The easiest way to do this is by mixing it in with the water. But most nutrient systems come in multiple parts because the chemicals in one will mix with the other and prevent the desired nutrient from being absorbed by the plant.

Novice growers often don't realize that mixing the nutrients in an order other than advised by the manufacturer is bad. It isn't until they have a plant in dire straits that they seek help and learn this hard lesson. When adding them to a plant, mix the additives one at a time to avoid chemical lockout.

And overfeeding can be just as harmful as anything else. Most of the nutrients a plant needs are salts but having too much salt in the grow medium can burn roots, shrivel foliage and even kill the plant if not corrected. Making sure to flush the plant with pure water once a week will help prevent nutrient buildup and keep plants healthy.

You also have to know when to stop feeding.When a female plant is ready to be harvested, any nutrients still trapped in the flowers will remain even after drying and curing the buds. Most experienced growers stop feeding their plant nutrients one to two weeks before they plan to harvest. The process is called flushing and is intended to remove the nutrients the plant uses to grow from the end product.

Failing to flush at least a week before harvest will result in weed that sparkles and crackles when lit. This indicates residual nutrients left in the flower and makes the smoke taste bitter and acrid. Clean cannabis never crackles or sparkles, it smolders into a white or light grey powder.

Getting to harvest is the hardest part of cannabis cultivation when something goes wrong but can seem like autopilot otherwise. But if you can keep the right ratio of nitrogen, phosphorus and potassium throughout the grow process, you will have amazing weed. It takes practice to get right but the effort is more than worth the reward.

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