7 Most Surprising Fertilizers Found In Your Kitchen

By Nikki Tilley | October 19, 2019
Image by Nikki Tilley
by Nikki Tilley
October 19, 2019

It’s no secret that as gardeners we all want healthy plants. While healthy soil is vital to this, fertilization plays a significant role too. But what if you don’t have lots of money to spend on plant fertilizer? That’s not a problem. There are actually a number of “fertilizers” that may already be available right at your fingertips – and they’re all found in the kitchen!

Here are 7 surprising household fertilizers that you can use in the garden that won’t cost you any extra:

Milk – Got milk? You probably didn’t know that milk isn’t just good for you but also your plants. In fact, using milk as fertilizer is an old-time remedy from long ago. It’s a great source of calcium but also contains beneficial proteins, vitamin B, and sugars that benefit plants, improving their overall health and yields. You can use fresh or outdated milk, evaporated milk, or even powdered milk. Just be sure to dilute it with water, at least 50/50. Use this as a foliar spray or pour around the base of plants where the roots will gradually absorb the milk. If using powdered milk, simply sprinkle into the soil and water in.

Gelatin – “Watch it wiggle, see it jiggle”¦” That’s right, I’m talking about Jell-O, or more specifically, unflavored gelatin. This is actually a great fertilizer for houseplants and other foliage plants in the garden. Why? Gelatin is essentially a form of collagen made from animal bones, skins, and the like, and is a great source of nitrogen, promoting healthy plant development and growth. You’ll want to dilute this with plenty of water – one packet to a quart of water (typically dissolving the package of gelatin in a cup of hot water, then adding 3 cups of cold water). Pour directly on the soil around your plants once a month.

Eggshells – Most of us know that calcium builds strong bones, but did you know that plants benefit from this nutrient too? Eggshells are loaded with calcium as well as small amounts of nitrogen, phosphoric acid, and other trace elements. As a fertilizer, this helps increase cell division and promote stronger, healthier growth. It can also help reduce blossom end rot in tomatoes. Wash and crush the eggshells (you can even toss in the blender and grind), and then sprinkle onto your garden soil or add them to your compost pile. Likewise, you can make your own calcium fertilizer spray. Fill a gallon jar with water and eggshells, steeping for about a month. Mix 1 cup of the solution with 1 quart of water in a spray bottle and use as a foliar spray. Note: You can also use leftover water from boiling eggs to attain the same results.

Cooking water – And speaking of boiling water, this too (cooled down, of course) can make an excellent fertilizer for garden plants. Water that’s been used to boil potatoes, vegetables, eggs, and pasta is actually filled with nutrients, such as phosphorus, nitrogen, iron, calcium, and others. Now, instead of pouring that useful cooking water down the drain, allow it to cool off and give your plants a drink. They will thank you for it with healthier growth. It’s especially beneficial to houseplants, but any plant can benefit from this low-cost fertilizer.

Coffee – Life wouldn’t be bearable without that morning coffee and your plants will appreciate it too. Using coffee grounds as a fertilizer adds organic matter to the soil, improving overall drainage, water retention and aeration. It also contains about two percent nitrogen. Coffee grounds are said to be good for acid-loving plants too. Just keep in mind that this is only true for unwashed coffee grounds – fresh grounds are acidic while used grounds are nearly neutral. The best way to use your coffee grounds is to compost them but you can also scatter them on top of the soil around your plants and water in. And, in addition to adding nutrients, if you’re wanting to give those acid lovers a boost, don’t toss that leftover coffee. Using diluted coffee as a fertilizer can increase the acidity of the soil since it has a pH of 5.2 to 6.9.

Bananas – Bananas are not only healthy for us, but they can benefit plants too. Bananas are an excellent source of potassium and great for soil. They can also provide plants with phosphorus. While some sources say to simply lay the banana peels directly on the soil to leach nutrients into the ground, it’s usually recommended that banana peels be composted first, generally cutting them up into smaller pieces where they can break down quicker. You can, however, forgo the composting and make a homemade liquid fertilizer instead. Just chop up all some banana peels, put them in a jar of water, and allow this to sit for about a week or so. Then water your plants with it, tossing those remaining peels in the compost heap.

Vinegar – Okay, we know that vinegar is great for many things, and in the garden, it normally makes a good organic herbicide, normally white vinegar. But what you likely didn’t know is that apple cider vinegar (with 5 percent acidity) can be used as a fertilizer to maintain healthy plants. That’s right! Just a tablespoon of vinegar (one tablespoon of vinegar to one gallon of water) can boost a plant’s defense mechanism, helping it fend off insect pests and microbes. It also accelerates germination and increases yields. Pour the diluted vinegar/water mixture onto the soil around your plants to help keep them healthy and happy.

BONUS: Just another helpful FYI for those of you having fish aquariums (freshwater only, no saltwater). As you’re cleaning out the tank, don’t toss that water. Instead, use it to give your houseplants some much needed love. It’s rich in beneficial bacteria, potassium, phosphorus, nitrogen, and trace nutrients that help promote lush, healthy growth. And the fish waste makes a great plant fertilizer too.

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  • Rootmax
    Comment added December 15, 2021Reply

    Thanks for sharing this information with us by blog so that people can better understand the Organic fertilizers Options available in the market and get the proper benefits in their gardens. For more details go to https://www.growmate.co

  • greg
    Comment added November 16, 2021Reply

    Hy Nikki Tilley
    Thanks for sharing this information with us by blog so that people can better understand the Surprising Fertilizers which can be Found In the Kitchen. I have some more useful information related to fertilizers on my site which helps to better understand fertilizers. here's the link https://www.growmate.co/blogs/news/five-major-benefits-of-organic-fertilisers

  • Mark
    Comment added June 4, 2021Reply

    Thanks, such a nice information. Humic acid is easily available in the humic matter of soils. It increases the microbial activity in the soils, improving the soil health. It also enables the uptake of nutrients, absorption of water, and also fights against various pests. Humic acid is a major component of humic substance, which are organic constituents of soil/humus, coal, and peat. It is also an organic constituent of various upland streams, ocean water, and dystrophic lakes.

  • Kirk McIntyre
    Comment added June 2, 2021Reply

    I thought about using fish water but I learned that the algae is VERY harmful and will kill the plants.

  • Daniel
    Comment added August 18, 2020Reply

    Very informative thank you very much

  • Jodie C Bell
    Comment added June 21, 2020Reply

    Can I use actual bananas? I have some that are way too ripe!

  • Karen Murphy
    Comment added January 1, 2020Reply

    Many useful tips, Thank you! I am printing this out for the spring. Last year I decided to try mixing vegetables with flowers for this coming year as in another one of your articles. I saved seeds from peppers, tomatoes, cherries, lemons and oranges. Someone said lemons are like pine trees but I don’t get it because they have to be brought in from the cold. Could you explain that one or was that wrong? Also I saved seeds from a dragon fruit and wanted to try to grow it. Any advice on this? I know it looks like a Christmas Cactus, do you treat it like a cactus? Thank you!

  • Bonnie
    Comment added November 21, 2019Reply

    I used freshwater fish tank water & ended up with knats in all my plants.
    Used potting soil also.
    What's up with the bugs?

  • Janalee S
    Comment added November 16, 2019Reply

    Be careful with fish water. It can be far too rich in named nutrients as I learned the hard way. Dilute, dilute, dilute!

  • Lyn
    Comment added November 6, 2019Reply

    Egg shells were always throwing into the chicken run or crushed for plants. Banana peels and most other fruit and veg peels/skins also went back into the garden or to the chickens, depending on the day. All on our Gran's strict instructions words of wisdom

  • Linda Westmoreland
    Comment added November 2, 2019Reply

    Great information. Vinegar is crazy stuff. It can be used in so many different ways around the home. I will be using some apple cider solution on some capsicum fruit as they seem to always get fruit fly.

  • linda novosel
    Comment added October 27, 2019Reply

    such interesting and useable tidbits!

  • Laura Egli
    Comment added October 27, 2019Reply

    Just brought my new gardenia bush indoors with high hopes (New York City). These articles are going to be very helpful. That also goes for any gardenia lovers who care to pass on some helpful survival tricks. It is placed about four feet from a very sunny west window, ... but there's a floor-length radiator between them (4ft.away too). Any advice will be so appreciated.

  • Pat
    Comment added October 26, 2019Reply

    I enjoy these articles very much! Many I already do or have done. One important tip, if you use egg shells and water be certain to open the container in the garage, or outside. The smell is extremely...”potent”. Take it from me...

  • Ann J Harris
    Comment added October 23, 2019Reply

    I really enjoy these articles. Have learned so much. Thanks, Ann, Ottawa, Ontario, Canada

    Comment added October 20, 2019Reply

    I Loved every word THANKS

  • Jackie Pate
    Comment added October 20, 2019Reply

    I think this is absolutely the best website and blog.

  • Mary Renaud
    Comment added October 20, 2019Reply

    This article is full of common everyday information that I never knew about, except for the eggshells. Thank you for writing about these home remedies. I look forward to testing these solutions with the resources that I didn't realize are in my home.
    Thank you for sharing your knowledge!

  • Tommy Carroll
    Comment added October 20, 2019Reply

    I,had not known,about these fertilizers in my cabinet..This was VERY helpful,as in the spring,I am going on a propagating adventure to see what I can root to sell the rooting for a little extra money..Anyone have any tips?Thank you...

  • Marti Shafer
    Comment added October 20, 2019Reply

    This article was so informative!
    Thank you so much!

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