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How to Make Hydroponics Nutrient Solution

Hydroponic systems are one way to grow vegetables, flowers and other plants during the winter. In a hydroponic garden, a synthetic medium like rock moss, vermiculite or perlite wicks up water with chemical nutrients straight to the plant roots--no soil necessary. All needed nutrients are in the hydroponic nutrient solution.

Although there are many commercial hydroponic nutrient solutions, mixing your own can help you develop a starting point for providing custom nutrients for your flowers or vegetables. Making a homemade nutrient solution is often cheaper than buying a commercial solution.

Put on rubber gloves, laboratory goggles and a filter mask. For the quantities you are mixing, a surgical mask commonly available at many pharmacies should be sufficient, as some of the below ingredients are unsafe to inhale. Wear an apron specifically set aside for the purpose of mixing nutrients.

Pour 9 ounces of potassium nitrate powder into a large metal pot or mixing bowl. Potassium nitrate is also called saltpeter. Potassium nitrate is a strong oxidizer and can be harmful if inhaled, swallowed or absorbed through the skin.

Pour 7 ounces of calcium phosphate powder into the mixing container. Calcium phosphate is often called plaster of Paris. Calcium phosphate can be harmful to lungs and mucus membranes.

Add 6 ounces of magnesium sulphate to your mixing container. Epsom salts are magnesium sulfate. Epsom salts come as a granular powder. Magnesium sulfate can be toxic if swallowed.

Add 4 ounces of monocalcium phosphate powder. Monocalcium phosphate can cause irritation to eyes, skin and mucus membranes.

Pour 1 1/2 ounces of powdered ammonium sulfate into the solution. Ammonium sulfate is the principal source of nitrogen in this recipe. Ammonium sulfate can cause irritation to lungs, eyes, skin and mucus membranes, so again, wear an appropriate mask.

Next, add 1/2 teaspoon of iron sulfate to the mixing bowl. Iron sulfate can irritate skin, eyes, lungs and mucus membranes. Chronic exposure over time can cause liver damage.

Mix the dry ingredients thoroughly by sifting them through your gloved fingers.

Place the dry ingredients in a well-sealing container with enough space to re-mix the dry ingredients before use.

Rinse your mixing bowl or pot carefully outside with plenty of water to dilute any chemicals remaining in the bowl.

Shake your ingredients to mix and add one teaspoon of dry ingredients to each gallon of water required by your hydroponics system. Mix the dry ingredients with the water until it dissolves. If your dry mix doesn't immediately dissolve, let the solution sit for several hours.


Always wear full protective equipment when mixing your pre-mixed nutrient powder with water.


Many of the raw ingredients in making the dry component of hydroponic nutrient solutions can be irritating to skin, eyes, and mucus membranes or may be toxic if swallowed. Be sure to use sound safety procedures and mix the dry ingredients either outdoors or in a well-ventilated area.

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