How to Make Your Own Fertilizer

Different at-home garden fertilizers on wooden surface

The Spruce / Phoebe Cheong

Project Overview
  • Working Time: 10 - 15 mins
  • Total Time: 10 - 15 mins
  • Skill Level: Beginner
  • Estimated Cost: $0 to $5

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

  • 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. Like any fertilizer, a little goes a long way! Be sure to use the correct dose for plant size.

    Epsom salt in glass bowl for garden fertilizer

    The Spruce / Phoebe Cheong

  • 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.

    Tip

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

    Used coffee grounds as garden fertilizer

    The Spruce / Phoebe Cheong

  • 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.

    Cracked eggshells as garden fertilizer

    The Spruce / Phoebe Cheong

  • 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.

    Creating a vinegar solution for plant fertilizer

    The Spruce / Fiona Campbell

    Tip

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

  • 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.

    Used fish tank water with foliage as garden fertilizer

    The Spruce / Phoebe Cheong

  • Employ Fireplace Ashes

    Collect fireplace ashes after they cool down. Sprinkle 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 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.

    Fireplace ashes in glass bowl for garden fertilizer

    The Spruce / Phoebe Cheong

  • 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 addition to your soil that can be used anywhere in the garden.

    Vegetable scraps in bowl as garden fertilizer

    The Spruce / Phoebe Cheong

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Quick Guide to Fertilizing Plants. UMN Extension.