6 Ways to Make Your Own Organic Fertilizer

I don’t like the idea of adding chemicals to our environment. And let’s be honest – if you are spending the time to grow your own fruits and vegetables you shouldn’t either. Synthetic chemicals and toxins, found in common pesticides, herbicides, and fertilizers are undisputedly bad for humans and the environment. Yet despite a mountain of scientific research that shows their harmful effects, over 80% of products sold in gardening centers still contain them. What’s worse – these products are marketed as “safe”.

I can talk for days about why I prefer not to use chemical herbicides and pesticides in my garden, but today let’s chat specifically about chemical fertilizers. Touted as a quick fix for soil, gardeners often overlook their harmful effects and that they are unnecessary for garden success. In fact, use of chemical fertilizers makes gardening more difficult as it diminishes soil health and repels beneficial organisms. Go figure.

What is fertilizer?

Fertilizer is a chemical or natural substance added to soil to increase its fertility. Essentially, plants need three major nutrients to thrive: Nitrogen (N), Phosphorus (P) and Potassium (K). You might see these displayed on commercially made fertilizers in number form, for example, 10-5-5. Nitrogen is necessary for leaf and green growth, Phosphorus for flowers and fruit, and Potassium for general health of the plant. Plants also need a lot of other nutrients as well, called Micronutrients. Some of these include Magnesium, Calcium and Sulfur. Plants are also affected by the acidity of a soil, and the biodiversity of bacteria that creates a healthy environment.

How to amend garden soil

Chemical vs. Organic Fertilizer

Many organic materials serve as both fertilizers and soil conditioners—they feed both soils and plants. This is one of the most important differences between a chemical approach and an organic approach toward soil care and fertilizing. Soluble chemical fertilizers contain mineral salts that plant roots can absorb quickly. However, these salts do not provide a food source for soil microorganisms and earthworms, and will even repel earthworms because they acidify the soil. Over time, soils treated only with synthetic chemical fertilizers lose organic matter and the all-important living organisms that help to build a quality soil. As soil structure declines and water-holding capacity diminishes, more and more of the chemical fertilizer applied will leach through the soil. In turn, it will take ever-increasing amounts of chemicals to stimulate plant growth. When you use organic fertilizers, you avoid throwing your soil into this kind of crisis condition.

shutterstock_376501138Fortunately, there are more and more organic fertilizers coming on the market. These products are made from natural plant and animal materials or from mined rock minerals. To identify these products in your garden center look for labels that read “natural organic,” “slow release,” and “low analysis”.

DIY Organic Fertilizer

I still occasionally buy organic fertilizer, but for the most part I like to make my own. Why? It’s cost-effective, easy to make, and produces great results. Beyond compost and worm castings, there are many other fantastic ways to make organic fertilizer from common household items. Let’s discuss further how you can make your own!

Banana Peels

High in potassium, phosphorus and calcium,  banana peels are great for flowering and fruiting plants. Simply bury a peel under the ground at the base of the plant, and allow to decompose. You can also freeze overripe bananas that you would have otherwise thrown away, and then bury next to a needy plant when needed. If you prefer to make a spray, soak a peel in water for 2-3 days, then use the water to spray plants or seedlings.

Banana Peel Fertilizer

Coffee Grounds 

Coffee grounds are a natural fertilizer that not only add nitrogen to poor soil, but also increase the acidity of soil. This will make your roses, hydrangeas, magnolias and blueberries especially happy! Work up to 25% coffee grounds into soil at the base of the plants. Coffee grounds will also improve the organic matter in the soil.

Coffee Grounds Fertilizer

Epsom Salt 

Epsom salt is available at your local drug store, and adds important magnesium and sulfur to the soil. Especially good for tomatoes and roses, Epsom salt tea is great for starting seedlings and reducing transplant shock as well. Known for giving plants a deep green color, especially on magnesium low soils, this is a simple and quick recipe. It is pretty impossible to over do this fertilizer, as it breaks down into a simple magnesium component.

Epsom Salt Tea Recipe

  • 1 Tablespoon Epsom Salt
  • 1 Gallon water

Mix the ingredients together and add to a watering can. The tea can be used for both indoor and outdoor plants. It can also be mixed into the soil around plants at a rate of 1 tablespoon for every 1-2 feet in height of plant.

Epson Salt Fertilizer

Grass Clippings 

Looking for a great organic fertilizer? Look no further than beneath your feet. Grass clippings are a rich source of nitrogen, oxygen and phosphorus for the soil. They can be added around the base of a plant, similar to mulch, or turned into a tea that can be poured into soil. (Thanks dad for teaching me this one!)

Grass Clippings Tea Recipe

  • 1 Five gallon bucket filled with fresh grass clippings.
  • Cover with water

Allow to sit for 3-5 days. Dilute the strained fertilizer tea by using one cup tea mixed with 10 cups fresh water. Pour onto soil.

Grass Clippings Tea

Compost Tea 

Made in exactly the same way as grass clippings tea, but with organic compost. This gives a much richer tea with a variety of nutrients, perfect for any plant.

Compost Tea

Egg Shells

Egg shells are very high in calcium, which is necessary for good cellular growth in all plants. If you have ever had blossom end rot on your tomatoes, then you probably have calcium deficient soil. You can crush up used egg shells and bury them beneath the surface of the soil.  For a faster response, you can make a spray.

Egg Shell Spray Recipe

  • 20 egg shells
  • 1 Gallon Water

Boil the egg shells in water for 5 minutes. Then take your pot off the stove and let the shells sit in the water overnight. You can strain the shells and use the liquid as a spray or the water can be added directly to the soil.

Egg Shell Fertilizer

I hope this post inspires you to consider organic fertilizers and even make your own! So spend a little time setting aside egg shells and coffee grounds. You will be saving yourself some cash, and creating a healthier environment for your plants and the planet! As always, happy gardening! 🙂

6 thoughts on “6 Ways to Make Your Own Organic Fertilizer

  1. HI Stephanie, really good post, thanks. I have heard people say though that the caffeine in coffee grounds inhibits plant growth because in the coffee plant it helps inhibit competing plants surrounding it, and therefore the grounds should be composted first rather than spread straight on the ground. Have you heard this or seen any effects either to support or oppose this view?


    • Hello there! That is really interesting – I haven’t heard that before but I’m curious to look into it. I have been using left over coffee grounds for quite some time and have never had an issue. I use them specifically on my hydrangeas, blueberries, and rose bushes. I’m wondering if people are referring to unused coffee grounds, as that would have quite a bit more caffeine than used coffee grounds. I would venture to guess that acidity is the main property left in used grounds versus caffeine. I will have to research this a bit more and if I find anything good I will post back on here! 🙂


  2. Pingback: How to Grow Epic Tomatillos

  3. Hello, i think that i saw you visited my web site thus i came to “return the favor”.I am trying to find things to enhance my web site!I suppose its ok to use a few of your ideas!!


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s