Here is a guide to making your own hydroponic nutrient solution. It will include a very precise recipe, and much easier, still effective homemade one.
To learn more about hydroponics check out hydroponics 101 and an introduction to general hydroponic systems.
To learn how to make your own, check out how to make your own homemade hydroponic system.
Okay, let’s begin!
THE VERY PRECISE NUTRIENT SOLUTION RECIPE
What You Will Need:
Equipment:
1) Two empty 1 Litre bottles
2) Two empty 5 Litre buckets/cans
Ingredients:
1) 10 L of hard/rain water
2) Calcium Nitrate (Ca(No3)2): 200g for fruit, 160g for vegetables, 110g for flowers
3) Potassium Nitrate (KNO3): 75g for fruit, 55g for vegetables, 75g for flowers
4) Sulphate of Potash (K2SO4): 45g for fruit, 12g or vegetables, 12g for flowers
5) Monopotassium Phosphate (KH2PO4): 37g for all
6) Magnesium Sulphate (MgSO4 * 7H2O): 64g or all
7) Chelated Iron (FeEDTA): 20g for all
8) TRACE MIX INGEDIENTS: You will be mixing some items together to create a trace mix. For fruit, vegetables and flowers, you will need these items in these amounts:
- Zinc Sulphate (ZnSO4): 2.2g
- Manganese Sulphate (MnSO4): 15g
- Copper Sulphate (CuSO4): 0.8g
- Boric Acid (H3BO3): 28g
- Sodium Molybdate (Na2MoO4): 0.25g
Putting It Together:
1) The first step is to make your trace mix solution. Take the 1L bottle and fill it half way with the hard water. Add the TRACE MIX INGEDIENTS from item #8 above one by one, letting them dissolve before adding the next one. Once finished, fill the bottle up to 1L. This will now be referred to as our TRACE MIX SOLUTION. It can be saved and used multiple times afterwards.
2) Next, we need to make an IRON CHELATE SOLUTION. Fill the second 1L bottle half way with hard water. Add the 20g of Chelated Iron from item #7. Fill the bottle up to 1L. This too can be used multiple times afterwards.
3) Take a 5L container, and fill it up with 4L of hard water. Add the Calcium Nitrate (item #2) and let it dissolve completely. Add the Potassium Nitrate (item #3) and let it dissolve completely. Add 100ml of the Iron Chelate solution. Fill the bucket up to 5L with water. This will be MIX 1.
4) Take your second 5L container and fill it up with 4L of hard water. Individually add the Sulphate of Potash (#4) Monopotassium Phosphate (KH2PO4) (#5) and Magnesium Sulphate (MgSO4 * 7H2O) individually, allowing each to dissolve fully before adding the next. Add 10ml of Trace Mix Solution. Fill the bucket up to 5L with water. This will be MIX 2.
The reason we make two solutions (Mix 1 and Mix 2) is to avoid certain chemicals from reacting with each other over time. The two mixes, as well as your trace mix and iron chelate solutions, can be saved for multiple uses. You now have enough ingredients to supply 100L of nutrient solution for your plants.
To use your nutrient solution, you want to create a mix of 90% water, 5% Mix 1, 5% Mix 2.
So to create 1L of nutrient solution, use 900ml of hard water, 50ml of Mix 1 and 50ml of Mix 2.
To create 10L, mix 9L of hard water, 500ml of Mix 1, and 500ml of Mix 2.
THE EASIER HOMEMADE NUTRIENT SOLUTION RECIPE
Okay, so that was pretty complex, and not everyone is itching to bust out their chemistry sets. Fair enough. This is a much simpler, but still effective, recipe for creating a homemade hydroponic nutrient solution.
What You Will Need:
Equipment:
1) A large bucket
2) Something to stir with
Ingredients:
1) A gallon of hard water
2) A good fertilizer that contains 20% nitrogen, 20% potassium, 20% phosphorous, and a good balance of the secondary and micronutrients plants need.
3) Epsom salts
Putting It Together:
1) Put a gallon of water into the bucket.
2) Add 2 teaspoons of fertilizer to the water. Stir.
3) Put 1 teaspoon of Epsom salts into the bucket, to add magnesium sulfate. Stir completely until everything has dissolved.
A NOTE ON CONCENTRATION OF NUTRIENTS
Different plants need different concentration levels to maximize their growth. Plants with similar nutrient concentration level requirements can easily be paired together.
Concentration is measured with a number called the Conductivity Factor (CF). Here’s a list of commonly grown vegetables, and their ideal CF range.
CF 8-12: Lettuce
CF 14-18: Peas
CF: 16-22: Carrots, Cucumbers, Leeks, Potatoes, Radish, Sweetcorn
CF 18-24: Beans, Beetroot, Broccoli, Brussels Sprouts, Cabbages, Cauliflower, Celery, Onions, Pumpkins, Spinach, Silverbeet
CF 22-28: Tomatoes
Conductivity factor can be determined by measuring the conductivity between electrodes in a water solution.
Good luck and stay prepared!

Hi, can I know where do you buy those chemical?
I’m sure chemical outlets or gardening outlets should have them.
Hi Rambo,
Let say there is no chemical shop at my local area, is there any homemade way to obtain secondary and micronutrients?
Thank!
Lee, I’m sure it is possible. Unfortunately it is a little bit outside of my range of expertise.
I am growing barley fodder for our dairy goats and was wondering if their is a way to increase the calcium level in my barley fodder, and any thing else that can be added so they get the most out of the fodder.
Thank you
Jack
I know adding crushed egg shells works to increase the calcium in composted material.
Hi Rambo,
For the “Easier method”, you said need to mix with epsom salt, can I know what is the reason for that? As I know, a good fertilizer with trace elements should be contained magnesium/sulfer ingredient.
Thanks!
@Jack: depends on the growing medium. If it’s soil, crushed egg shells work well. If it’s a liquid solution, you may need to get hold of calcium in liquid form. There may be another trick (ie would some form of milk work?) but none that I know of.
@Lee: yeah, check the specs, if the fertilizer has enough then you’re covered. If not, Epson salts are a way to increase the magnesium sulfate content. Depends what your growing, most plants won’t need much. Things like roses, tomatoes and potatoes need more, so adding Epson salts is a good idea.
Great for no cheap no fuss nutrient.
Any post-use / regular use steps to deal with salt buildup? ( like a 50/ 50 every 2 weeks? )
How about an “organic” fish emulsion based recipe?
@Frank: 50/50 every 2 weeks sounds good.
A fish emulsion fertilizer is a good idea, as is a fertilizer made of fish waste.