Hydroponic cultivation is all about control, so it’s unsurprising that a growing number of hydro-enthusiasts are turning to DIY hydroponic nutrients for their setups. But with all of the readymade nutrients out there, why would you want to go through the effort of making your own DIY hydroponic formula?
As great as they are, premixed nutrients are costly. Moreover, as you become increasingly well-versed in the art of hydroponics, you may want to customize your nutrient formulas to optimize the growth of your plants.
In theory, this sounds great, but putting it into practice can feel rather overwhelming. For this reason, we’ve compiled a comprehensive post discussing the basics of DIY Hydroponic nutrients, the equipment you’ll need, and more.
Table of Contents
Equipment needed to make DIY hydroponic nutrients
To begin, here is a list of general items that you will need to make your DIY hydroponic formula:
- Bucket, tub, or another container (view on Amazon)
- Accurate scale. (view on Amazon)
- Gallon jug or large measuring cup. (view on Amazon)
- pH test and adjustment kit. (view on Amazon)
- Electrical conductivity (EC) meter. (view on Amazon)
- Stirring rod or spoon.
- Gloves. (View on Amazon)
Essential elements of DIY hydroponic nutrient solutions
Plants require 13 essential elements for their growth – you will be using these elements as part of your DIY nutrient formula. In addition to these elements, they need carbon (C), hydrogen (H), and oxygen (O), which come from water and air.
These elements are categorized into two groups:
- Macronutrients: Macro elements that are required in larger amounts.
- Micronutrients: Trace elements that are required in smaller amounts.
The following table illustrates the 13 essential elements and groups them.
|Nitrogen (N)||Iron (Fe)|
|Phosphorus (P)||Manganese (Mn)|
|Potassium (K)||Copper (Cu)|
|Calcium (Ca)||Boron (B)|
|Magnesium (Mg)||Zinc (Zn)|
|Sulfur (S)||Molybdenum (Mo)|
But how and where do you source these elements?
Fertilizer salts are the answer. You can buy these online, from food stores, or your local nurseries/garden centers.
The most essential fertilizer salts for DIY hydroponic nutrient solutions are:
- Magnesium Sulfate/Epsom Salts: These contain magnesium and sulfur. Magnesium is a component of chlorophyll and is involved in the process of distributing phosphorus throughout the plant. Sulfur is responsible for the production of plant energy and facilitates the use of other elements.
- Potassium Sulfate: This provides potassium and sulfur. The plant uses potassium to produce energy from photosynthesis.
- Potassium Nitrate: This supplies nitrogen and potassium. Nitrogen is necessary to create stems, leaves, and plant cells.
- Superphosphate: Phosphorus and calcium come from this. Increasing phosphorus levels during bud development can improve yields as plants use higher phosphorus levels during this development stage. Calcium facilitates root growth and helps the plant absorb potassium.
- Trace Elements: Additional elements required for plant development. They include boron, chlorine, copper, iron, manganese, molybdenum, and zinc.
Related reading: Everything you need to know about vertical aquaponic systems
Importance of pH for DIY hydroponic formulas
Understanding pH for hydroponics is critical. The pH scale measures the relative acidity or alkalinity of a solution or a medium. This scale ranges from 0 (extremely acidic) to 14 (extremely alkaline)
Plants mostly prefer slightly acidic conditions that range between 5.8 and 6.5
The pH level affects the plant’s ability to absorb essential elements from the nutrient solution. Additionally, it influences the solubility as well as the capacity of the nutrient solution to retain its essential elements.
With the above in mind, it is incredibly important to test the pH of the water you are using for your DIY hydroponic formula and, ultimately, your nutrient solution as a whole.
Electrical conductivity of DIY hydroponic nutrients
After you have adjusted the pH level, it is time to pay attention to the electrical conductivity.
Electrical conductivity measures the concentration of the nutrient solution based on its ability to conduct electricity. Pure water does not actually conduct electricity. Only water with solutes (elements) added to it can do this.
To measure your solution’s electrical conductivity, you will need an EC meter. This special meter measures the electricity the nutrient solution conducts, which is directly related to the total dissolved solutes in the solution.
The scale is commonly expressed as millimhos (mmhos)or millisiemens (mS).
Your EC should bet between 0.8 to 3.0 mMhos, though in most cases, 1.5 to 2.5 mMhos is more appropriate. If you find that the EC is too high, you should add more water to bring it down.
For best results, test your solution as soon as you make it. Make a note of this value and then test and record the EC daily. Doing this will allow you to identify and remedy any weakening of your solution over a period of time.
General DIY hydroponic nutrient formulas
The nutrients below make up general-purpose DIY nutrient mixes. These mixes are used for the vegetative, flowering, and fruiting stages.
Please Note: These nutrient amounts are scaled to 1 US gallon of solution. You will need to adjust quantities accordingly if you plan to scale up.
Vegetative stage formula
|0.40||7% Fe Chelated Trace Elements – see below|
Flowering stage formula
|0.40||7% Fe Chelated Trace Elements – see below|
Fruiting stage formula
|0.40||7% Fe Chelated Trace Elements – see below|
Chelated trace elements
You must add these together and mix them into a fine powder before you add them to the above formulas.
- Iron (7%)
- Manganese (2%)
- Boron (1.30%)
- Zinc (0.40%)
- Copper (0.10%)
- Molybdenum (0.06%)
Mixing your nutrients
Now it’s time to assemble everything and create your DIY hydroponic nutrient mix. Here are the steps to do so:
- First, fill your container/s with the appropriate amount of warm water.
- Test the pH level of your water and its total dissolved solids. Your pH level will change as you add elements, so keep these readings. They will help you find the real concentration levels after your final reading.
- Add your measured-out salts for each compound, one at a time, and allow each to dissolve before adding the next one.
- Once you’ve added everything, let your solution stand until fully cooled.
- Now test and compare your pH against your initial reading.
- Adjust your pH so that it’s suitable for your plants.
Signs of nutritional deficiency and how to remedy them
While a DIY hydroponic formula can assist you in catering to the specific needs of your plants, it also means added responsibility. If you do not get the balance of nutrients right, your plants will suffer.
Fortunately, plants – much like humans – show visible signs of strain if they are suffering from an imbalance of nutrients. Both their growth and general well-being will be affected.
Some of these signs include a reduction in vigor, strength of the stems, and the color of the leaves. You’ll also end up with poorer yields.
Two sets of elements are responsible for symptoms in plants. They are:
- Mobile Elements – symptoms first seen on the older leaves
- Immobile Elements – symptoms first seen on the younger leaves at the top of the plant.
Here is a table illustrating the various mobile and immobile elements:
|Mobile Nutrients||Immobile Nutrients|
|Nitrogen (N)||Calcium (Ca)|
|Phosphorus (P)||Sulfur (S)|
|Potassium (K)||Boron (B)|
|Magnesium (Mg)||Copper (Cu)|
|Chlorine (Cl)||Iron (Fe)|
|Molybdenum (Mo)||Manganese (Mn)|
Related reading: Hydroponics With Fish (An Intro To Aquaponics)
- Symptoms: Lower leaves become yellowish-green, and growth is stunted.
- Remedy: Add calcium nitrate or potassium nitrate to the nutrient solution.
- Symptoms: Stunted growth, distinct purple color on the undersides of the leaves, and leaves fall off prematurely.
- Remedy: Add monopotassium phosphate to the nutrient solution.
- Symptoms: Older leaves have interveinal (between veins) chlorosis from the leaf margins inward. Necrotic spots also begin to appear.
- Remedy: Apply a foliar spray of 2% magnesium sulfate, or add magnesium sulfate to the nutrient solution.
- Symptoms: Upper leaves start to yellow. This progresses to leaf tips. Margins wither, and petioles curl. The growing point no longer develops, and the smaller leaves turn purple-brown at the margins. The leaflets remain tiny and deformed.
- Remedy: Apply a foliar spray of 10% calcium nitrate solution, or add calcium nitrate to the nutrient solution.
- Symptoms: Upper leaves become stiff and curl down, while the leaves begin to turn yellow. Plant growth is restricted, and the stems, veins, and petioles begin to turn purple.
- Remedy: Add potassium sulfate or other sulfate compounds to the nutrient solution.
- Symptoms: The terminal leaves start turning yellow at the margins and progress through the entire leaf, eventually resulting in necrosis. Initially, the smallest veins remain green, producing a reticulated pattern. Flowers begin to abort and fall off, and growth is stunted and spindly in appearance.
- Remedy: Apply a foliar spray with a 2%-5% solution of iron chelate every 3-4 days or add iron chelate to the nutrient solution.
- Symptoms: The growing point withers and dies. Upper leaves curl inward and are deformed, showing interveinal mottling (blotchy yellowing patterns). The upper, smaller leaves become very brittle and break easily.
- Remedy: Apply a foliar spray of 1%-25% borax solution, or add borax or boric acid to the nutrient solution.
- Symptoms: Young leaves remain small, margins turn into a tube toward the midribs in tomatoes, petioles bend downward, and growth is stunted, giving off a “bushy” appearance at the top of the plant.
- Remedy: Use a foliar spray of 1%-2% solution of copper sulfate or add copper sulfate to the nutrient solution.
- Symptoms: Middle and younger leaves turn pale and develop a checkered pattern of green veins with yellowish interveinal areas. Later, small necrotic spots form in the pale areas. Shoots will become stunted.
- Remedy: Apply a foliar spray of 1% manganese sulfate solution or add manganese sulfate to the nutrient solution.
- Symptoms: Older and terminal leaves are abnormally small. The plant may get a “bushy” appearance due to the growth slowing at the top.
- Remedy: Use a foliar spray with 1%-5% zinc sulfate solution, or add zinc sulfate to the nutrient solution.
Related reading: How To Grow Hydroponic Basil (Complete Guide)
When it comes to the nutrients for your hydroponic system, what you put in is what you get – that goes for both personal effort and nutrient quality.
Initially, the DIY route may seem a bit challenging. But once you’ve done the research and gathered all of the necessary materials, you’ll be able to forge ahead with creating your own DIY hydroponic nutrients.
Don’t be upset if you make a mistake or two along the way; it’s all about learning. Rest assured, once you’ve mastered the art of making your own nutrients, you’ll be better off for it!