Do you remember in elementary school when you started learning about how to take care of plants in class? Water and sunshine, are the two main ingredients. The plants get all of their energy and nutrients from the sun and the roots drink the water, but really there is so much more to it. The plethora of information on the needs of plants is very literally the difference between an elementary school biology project and a PhD in horticulture.

Turns out, plants really aren’t much different than us. We share 99% of the same DNA as the lettuce in our salad and 50% of the DNA in a banana. We also share the same dietary needs as plants and much like our health, you can survive with an unhealthy diet, but you would be the best version of yourself if you gave yourself the healthiest blend of nutrition that you can.

Plants have a surprisingly complex diet. They eat the blood and bone meal that they find buried in the ground, they consume the dead plant material that they shed each year in the fall, they use the silica found in sand, the pre-digested nutrition from animal poop, the microbes found in earthworm casings, and even consume fish bone if they have access.

This will help you to understand what they need and when. Advanced growing tips, as they come, will tell you how the plants use each ingredient, why they use each one, the slow and quick release versions of nutrients and the science behind synthetic nutrients vs organics.

NPK
These are the three numbers present on the bottle of your nutrients. The Nitrogen – Phosphorous – Potassium content of each product. NPK isn’t everything. It’s a guideline at the very least to allow yourself a quick look at the big nutrients and how they stack up in a nutrient regimen. It’s also a little cheat sheet to roughly guess whether or not a nutrient line is organic. The high numbers, in almost every case, represent a synthetic form of the nutrient. There’s a tool for every job, but it is nice to know if you are looking. There are amazing organic fertilizers out there that contain almost none of these main numbers and effective synthetic nutrients that have a high NPK of 0-52-32. The common trend, for whomever needs to hear it, is that the label of the Vegetative bottle in each line is almost always green, and the Bloom is usually a purple or red shade. To lend some guidance when looking at shelves of overwhelming options.

Nutrients for Growth
In the Vegetative stage of the cannabis plant, your plant will undergo rapid growth and will need the nutrients to maximize that process and to maintain optimal plant health. In this stage of their growth, they require higher amounts of Nitrogen along with a constant source of Calcium, Magnesium, and Phosphorous to stay well fed during and a healthy color of green.

You’ll see the common trend in Nutrients where the Nitrogen number in the NPK is higher in the Grow or Vegetative formula than the bloom solution.

Soil Amendments
There are soils at your local hydro store that are formulated for Cannabis and plants similar. If you are looking for a soil that will feed your plant the necessary nutrients then consult with your store and be prepared to tell them the size of the container you are growing in, how often you water, and how long you will grow them in that container before you transplant into a larger one. The reason they should be asking you these questions is to help you time out when or if you will need to transplant and how much to water. The soils will run out of nutrients through plant consumption and wash out after about 3 weeks on average, then you can either start adding liquid fertilizers to the plants, or plant them in slightly larger containers to introduce new soil
which will introduce new soil amendments.


Fertilizer
Each nutrient line is well established and set up with a Grow and Bloom version of the Base fertilizer. Sometimes lines will have a Grow A and Grow B. In these 2-part lines, the nitrogen is usually separated into the Grow A so that you have more control over the dosage, but a safe bet for anyone unsure of how much control they really need is to use equal parts of both bottles, usually 1tsp (5ml) of each per gallon of water.

Organic fertilizers will usually only be a 1-Part line. You will still always want to have a bottle of Cal-Mag (calcium magnesium) around to add to the water in any nutrient line, organic, synthetic, liquid, or powder.

The best advice that I can give is not to wait until you start seeing yellowing or burning in your plant to start feeding nutrients. If you are worried about putting too much in, start at half of the recommended dose and build your way up over the course of a couple of weeks as the plant happily responds. A calcium deficiency exists in your plant 2 weeks before it starts to show outwardly, and the damage will not repair itself it occurs. Your plant can have healthy new growth, but the damaged leaves will always be damaged and the deficiency will hinder your overall growth in the Veg state.

Nutrients for Blooming

Soil
The same basic principle applies to both plants that are in Veg and plants that are in soil for blooming. You will want to transplant into your final pot size a few days before you initiate flowering. The biggest and most important difference is that you cannot, should not, and will not have good results if you transplant into another container in the flowering cycle. The plant will immediately halt all bud production to re-establish root growth and recover from transplant shock. Once your soil, if you are using amended soil, runs out of nutrients within the first three weeks, you will need to supplement a fertilizer in your watering process. That being said, I still advise that you consider using Cal-Mag supplements even during the first three weeks to keep your plant from becoming deficient during its phase of bud production.

Fertilizer
You will need nutrients for a successful harvest. They can survive with very little, but you will see greener plants and much larger bud sites when they are well-fed. There are very easy options in which you can just sprinkle on some nutrients and water it in with your regular water which is called top-dressing. The other way is to mix your water-soluble powdered nutrients or your liquid nutrients into a bucket or reservoir and water your plants with that. The benefit of adding the nutrients into your reservoir is that you can add exactly what you need and prevent any over or under-dosing. You also can more easily follow the nutrient feeding charts that your
nutrient line recommends having a consistent harvest each and every time.

During the Bloom Phase, your plant will need very little nitrogen and very high phosphorous and potassium to start bulking up the way they have the potential to.

These are the basics that you can absolutely grow without. I will say that they do help tremendously and if you’ve already gotten to this part in the article, you can’t unread it now.

I started a very long time ago with a starter kit of nutrients and a print-off feeding chart, it was a long time before I stumbled upon the NPK meanings and uses because the scientists that created my nutrients and told me how much to put in and when to use each bottle. They had already balanced the line and made sure I didn’t need to do much homework if I didn’t want to. I did want to, but not everyone has the time, want, or need to.
See what your friends are using, ask what the pros are doing, and get the right fertilizers and
schedule for you. They all work and they are all surprisingly different from each other and
produce a very different product. If you get bored, try new things, if you don’t bore easily, stick with
a good balanced line and just upkeep your environment.

As always, happy growing and call us if you need anything!

Olivia Sobelman has been a cannabis grower for over a decade and was part of a team that won the US Cannabis Cup Awards three times. Sobelman and her husband, Tyler, own and operate The Grow Depot Hydroponics Store in Missouri. Fast becoming “The Plant Doctors,” the Sobelmans’ mission to educate and destigmatize cannabis is at the root of their business. Grow depot offers access to free consultations for patients and growers, both in-person and by phone, to diagnose and mend many issues in the garden. Visit Grow Depot for grower tutorials, past articles, and to learn more about the services they offer and their contributions to the cannabis community.

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