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What Is Plant Food Made Of?

tropical plants image by Diane Stamatelatos from

Commercial plant food is made from a combination of three key ingredients: nitrogen, phosphate and potash. The amounts and ratios of each ingredient varies depending on the type of plant or flower to be fed.


Nitrogen promotes leaf growth and lushness. Phosphorus aids in producing strong roots and increasing fruit development. Potash is made from potassium which enhances the color of flowers and helps to increase size and strength. Commercial plant food is available in several formulas labeled with the percentage of each of these ingredients.

Finding the Right Mix

Do some research to find out which formula is best for your plants and read plant food labels before purchasing. A careful schedule should be followed as feeding a plant too often can be as detrimental as feeding it too little.

Making Your Own

Some gardeners prefer the eco-friendly alternative to commercial plant food: making their own from compost or a mixture of epsom salts, saltpeter, ammonia and baking powder.

Plant Food

Measure approximately one cup of plant food for every pound of soil. Ensure that the plant food mixes evenly throughout the soil. Fill a watering can with a gallon of water. Water the soil around the plant per the requirements for the specific type of plant. Place the plastic top on the head of the spike. Press the fertilizer spike into the ground at a 45-degree angle facing toward the plant. For larger tree spikes, this may require the use of a hammer.

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