Let’s face it, purchasing nutrients can get expensive. There are many different manufacturers selling nutrients at your local hydroponics shops and finding the ones that work best for your situation can include some trial and error. We would like to save you some money by avoiding the buying of nutrients that are too general purpose and focusing on the nutrients that are made for fast growing annual plants like cannabis.
To grow to their heaviest, full potential, your plants need 16 elements. But if you want the best results, you’ve got to have the best versions of each of these. And in the right amounts. Our nutrient info below is broken into 2 parts, chemical based nutrients and organic nutrients.
This chart shows the average PPM of each element needed for growing Cannabis indoors as well as typical ranges:
If you are growing hydroponically you will probably be using chemical fertilizers. The number of companies manufacturing chemical nutrients can be blinding. However, there are general purpose manufacturers and there are also some companies that make nutrients that are intended for cannabis cultivation. We are going to skip right over the general purpose manufacturers to avoid wasting your time reading about things that you don’t care about.
Both chemical and organic fertilizers separate their nutrients based on the growth stage of the plant. In addition to this, there are many additives that you can purchase that will help you fine tune your feeding by adding in these supplemental nutrients. Some varieties of cannabis will require slightly more of one or more elements in the different phases of growth and these supplemental nutrients will help get you where you need to be. You can also push some cannabis varieties during the flowering cycle by tweaking the nutrient solution with additives.
If you are growing in soil or an inert medium like peat, you might try using organic nutrients to help preserve the earthy richness and flavors in the plants you are growing.
There are some things that you will need to pay attention to when purchasing organic nutrients that you don’t need to worry about when purchasing chemical nutrients. Organic nutrients can go bad, so you will want to avoid purchasing products that have been sitting on a shelf for a while. An organics only grower friend of ours started having a problem in the garden that appeared to be a nutrient deficiency. The problem was showing up in the grow room as well as in many different house plants. Through trial and error and lots of head scratching he finally switched over to a regular chemical fertilizer and the plants all started to come back online. He then went and purchased some fresh organic nutrients and that resolved all of the problems. So keep shelf life in mind when shelling out big dollars for organic nutrients.
Different Plants have Different Nutrient Needs
The most important thing about nutrients, whether you decide to use chemical or organic based fertilizers, is how much to use. Most fertilizers purchased in specialty gardening shops will have recommended dosage instructions which may or may not be right for you. Different varieties of cannabis for instance will have different nutritional requirements with some being able to take significantly higher quantities than others. Using the instructions on the bottle may be toxic for your variety. So the best practice if you are unsure is to start light and use a mixture of around 150 ppm if using a chemical fertilizer and growing in an inert medium like peat and apply once a week. Then instead of increasing the ppm, increase the frequency if deficiencies start to appear. Also, be aware that different sized plants will also have different needs, a large plant will need more than a small plant.
Don’t try to wing it by scheduling feeding by memory, you will fail. Print out a 3-4 month calendar and hang it in the garden. Keep an exact accounting of what was done on each day. Keep track of things like if you used nutrient or plain water, if you applied a mycorrhizae solution, when you transplanted to larger containers, when you adjusted light schedules, and when you notice deficiencies or signs of over fertilization. Keeping a specific accounting day by day will make you more successful in future sessions.