In this blog, you will learn, what are hydroponic nutrients and their ratios and how to mix them correctly.
Hydroponic nutrients are the key to hydroponics.
Hydroponic nutrients are an important factor in plant growth.
The hydroponic system uses more water and shows huge efficiency because they are water based. Because they use water as the main delivery method of nutrients to plants.
Because nutrients are more directly available to plants, hydroponic systems can eliminate bottlenecks to production that are involved in nutrients. This increases the growing capacities of these types of systems.
It also maintains nutrient management of plants. So, what is exactly nutrient management means?
Good hydroponic nutrient management occurs when cultivators are :
Providing correct ratios of nutrients to plants
Providing advocate amounts of nutrients to plants
Getting to know where nutrients come from
Monitoring and measuring each plant nutrient at any given time
Making economic and workflow conscious decisions about nutrients
This thing makes cultivators achieve their growth and now we are going to talk about plant nutrient needs, how to measure and monitor them, and the factors for making wise fertilizer choices.
16 plant nutrients and where plants get them
Most plants (and all of the crop plants that you’re likely to grow) depend on 16 nutrients to grow and reproduce. Of these, three are available through water uptake and gas exchange (the air): Carbon through CO2, hydrogen, and oxygen. Growers should be thinking about air movement and dissolved oxygen levels in the fromwater, irrigation timing, etc., but generally, these practices are considered separately of hydroponic nutrient management.
The remaining thirteen nutrients are the mineral nutrients delivered to plants through hydroponic nutrients dissolved in a solution. We can separate them into 3 groups:
Primary macronutrients, the most abundant building blocks in plant growth and reproduction.
Secondary macronutrients, are also necessary, but in smaller amounts.
Micronutrients, are required in very small quantities for growth and reproduction.
Primary macronutrients: N, P, K
The primary macronutrients are nitrogen, phosphorus, and potassium, or NPK.
Nitrogen is important for all kinds of molecules involved in photosynthesis and protein creation. It is supplied either all at once as in liquid fertilizers, or in two parts (an NPK mix and CaNO3) as in dry fertilizers.
Phosphorus is especially important to cell membranes and is supplied in the main nutrient mix, whether dry or liquid.
Potassium is key to signaling compounds used in plant growth and development in all stages, and like phosphorus is delivered in the main nutrient mix.
NPK is the main nutrients to plants in hydroponics.
Secondary plant nutrients: Ca, Mg, S
The secondary plant nutrients are calcium, magnesium, and sulfur.
Calcium is important to cell walls and is an important structural element. Calcium which interacts uniquely with other nutrients is much less soluble than the other nutrients and can cause precipitation (when dissolved solids recombine to create solids in a solution). This means that it must be mixed separately. It is supplied in calcium nitrate, CaNO3.
Magnesium is important to the photosynthetic complex and is supplied in magnesium sulfate, MgSO4, also known as Epsom salt, as well as the main nutrient mixture.
Sulfur is important in peptide bonds, which
are present in all kinds of biological molecules. It is primarily delivered in MgSO4 alongside magnesium.
Micronutrients
The micronutrients are:
Boron (B)
Chlorine (CI)
Copper (Cu)
Iron (Fe)
Manganese (Mn)
Molybdenum (Mo)
Zinc (Zn)
Without micronutrients, plants will not survive for a long time.
Measuring nutrients with EC
The hydroponic nutrients are measured with EC
EC measures how well a solution transmits electricity. This works because:
All mineral nutrients are salts and dissolve to become ions in a solution.
Ions in a solution make it more conductive.
So when we measure the conductivity of a solution, we are effectively measuring the nutrients in that solution.
An EC meter uses two metal probes to measure conductivity. A current is passed from the probe to probe in the water and the strength of that current is measured, then translated into a measurement of how many salts are in the water.
The units used to measure EC are ppm or mS/cm, although ppm is used more commonly for measuring total dissolved solids. Hydroponic growers really need to understand the second unit, mS/cm. This is often just expressed as the “EC level”. For example, “The EC of the solution is 1.8,” with no unit.
Ideal mS/cm values are typically between 1.2 and 3.3. There’s a broad range of acceptable EC levels, and each crop has an ideal range. To find a range where all of your crops overlap, check out the Hydroponic Help Cards or the EC Management Card, which list the ideal EC for crops.
Nutrient ratios & formulas
All fertilizers are formulated in certain ratios. Different crops and crop types require nutrients at specific ratios. Using the correct ratio helps growers to avoid deficiencies or toxicities, and keep nutrient solutions balanced over time
For Example Leafy greens formula 8-15- 36
Mixing Instructions for 3.785 Liters of water
(For full strength working solution)
For 3.785 liters, swap out the “lbs” for “tsp” below.
Nutrient availability based on pH
Supplying the correct nutrients is only half of the nutrient management picture; the other task for farm managers is to keep those nutrients available to plants, and the main factor influencing the availability pH
Nutrients are soluble at different pH values.
Optimal pH is usually between low 5’s and low 6’s. Some crops prefer it a bit higher or lower, so you’ll have to check your crop. (The Recommended Crop List also lists pH ranges.)
Adjusting pH to your ideal range can be done with pH Down or pH Up, which are acids or bases Follow the below steps while adding this.
1) Don’t use both an acid and a base at once or you’ll just be fighting yourself. It’s counterproductive!
2) Don’t use crazy additives like lemon juice or vinegar. Use commercially proven products. If you must use something else, please contact us first so we can guide you away from potentially costly mistakes!
Types of fertilizer: dry vs. liquid
There are two main forms of fertilizer: dry and liquid.
Dry fertilizer is mostly used in commercial settings because there’s a lot less to ship (you’re not shipping water), making it more cost-effective. You can also tailor dry fertilizer better to your needs because it comes in separate parts.
Dry fertilizer usually comes in 1, 2, or 3-part mixes. We use a 3 part mix:
Part A is NPK, most of the macro-and micronutrients—basically all of the salts that dissociate easily and are very soluble.
Part B is calcium nitrate (CaNO3), the main source of calcium and nitrate. It’s not very soluble so we keep it and mix it separately.
Part C is magnesium sulfate (MgSO4), and the main way that we supplement sulfur in our system. This is also called Epsom salt and is very soluble.
Liquid fertilizer is simple to use and great for home and hobby systems. It’s easier to manage since you can just add a certain amount of one liquid to your system water, but it’s more expensive to ship. (Most people on a small scale only buy a little at a time though, so shipping is less important.)
Mixing Tips
The best way to mix a solution is to follow the manufacturer’s instructions.
The manufacturer will always send mixing instructions, and this is the best place to start. Over time you can tweak the process a bit for your specific crop and situation.
In conclusion: get an edge on hydroponic management
You’ve learned about the 13 mineral nutrients, measuring EC and pH, types of solutions, mixing solutions, and tools to manage nutrients. This should put you on the right road to being a great hydroponic manager.
Of course, there’s always much more to learn!
To learn in-depth about Hydroponics, Join our Modern Hydroponic Certificate Course.
