How to Make Your Own Fertilizer

Gardener spreading fertilizer

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Project Overview
  • Working Time: 10 - 15 mins
  • Skill Level: Beginner

Want to do right by your plants but don't want to spend too much money on fertilizer? Here are seven homemade fertilizer recipes for you to put to the test. They're made from ingredients you probably already have on hand, including some things you may be in the habit of throwing away. Read through the instructions carefully to determine if a particular fertilizer is right for your needs; for instance, some homemade fertilizers shouldn't be used on acidic soil, while others shouldn't be used on alkaline soil.

Keep in mind that you will not need all the ingredients in the supply list or all the items in the tool list. Choose your ideal homemade fertilizer and read those instructions to determine which of these items you'll need to create your plant food.

What You'll Need

Equipment / Tools

  • Watering can
  • Cookie sheet
  • Blender
  • Compost bin

Materials

  • Water
  • Epsom salt
  • Used coffee grounds
  • Newspaper
  • Eggshells
  • White vinegar
  • Water from a fish tank
  • Fireplace ashes
  • Fruit and vegetable scraps

Instructions

  1. Make Epsom Salt Fertilizer

    Dissolve 1 tablespoon of Epsom salt in 1 gallon of water. Shake the solution thoroughly. Use the solution to water your plants. Water them with this solution once per month during the growing season.

    It works because Epsom salt is made up of magnesium and sulfate – both vital plant nutrients. Some magnesium-loving plants to try it on include houseplants, roses, peppers, tomatoes, and potatoes. Use this fertilizer in place of rose plant food, vegetable fertilizer, or houseplant food.

  2. Try Coffee Ground Fertilizer

    Line a cookie sheet with newspaper. Spread your used coffee grounds out on the sheet, and allow them to dry completely. Sprinkle the grounds around the base of your acid-loving plants.

    This works because coffee grounds are rich in nitrogen, magnesium, and potassium – all-important plant nutrients. They're also naturally acidic, so they can help you boost the acidity of the soil. Azaleas, roses, rhododendrons, and blueberries are just some of the plants that will benefit from this treatment. Use this in place of rose plant food and soil acidifiers.

    Tip

    Be careful not to overdo it with the grounds. Even acid-loving plants can get too much acid.

  3. Use Eggshells as Fertilizer

    Save your eggs shells and allow them to air dry. Place the dried shells in a blender and pulse until they're powdery-fine. Sprinkle the shell powder around the plants in your garden.

    This works well because eggshells are made up almost entirely of calcium carbonate – the main ingredient in agricultural lime. Use this in place of lime in the garden.

  4. Create Vinegar Fertilizer

    Combine 1 tablespoon of white vinegar and water. Use the solution to water your plants. Repeat every three months.

    This works because the acetic acid in vinegar works to increase the acidity of the soil—just the thing for acid-loving plants. Use this in place of houseplant fertilizer, rose plant food, and soil acidifiers.

    Tip

    Never use straight vinegar to fertilize your plants. Undiluted vinegar is an herbicide.

  5. Use Fish Tank Water

    Simply save the water from your fish tank the next time you clean the tank. Use it generously and often to water any plants.

    This works because used fish tank water is full of nitrogen and other nutrients that plants need to thrive. This can be used in place of any other type of fertilizer.

  6. Employ Fireplace Ashes

    Collect fireplace ashes after they cool down. Sprinkle these cool (never hot) fireplace ash over your garden beds and work it into the soil.

    Fireplace ash is rich in potassium and calcium carbonate. If your soil is too acidic, it'll help to balance out the pH, so your plants are better able to absorb the nutrients that are present in the soil. Use it in place of basic garden fertilizer and garden lime.

    Tip

    Fireplace ash should not be used if your soil is alkaline. It also shouldn't be used around acid-loving plants, unless you're trying to turn hydrangeas pink.

  7. Make Your Own Compost

    Save your fruit and vegetable scraps, newspapers, grass clippings, and other compostable materials. Use them to start a compost bin or pile. Add a bit of water from time to time, and turn your pile to speed up the composting process.

    When everything has broken down into a dark, rich soil, it's time to spread it in your garden.

    Compost is loaded with nutrients and microorganisms that are good for your garden. It is a top-notch organic fertilizer that can be used anywhere in the garden.

Salt rock in a wooden bowl.

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Used Coffee Grounds

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Carton of Egg Shells

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A gallon jug of vinegar in a garden.

Erin Huffstetler

Boy Feeding Fish in Fish Bowl

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Man Cleaning Ash Out of Fireplace

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Compost Bucket

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