Growing crops in your backyard can save money, provided you go about it right and manage your soil. Crop rotation is one method, but if you only have a small backyard or vegetable garden, chances are, year after year, your plants are depleting the soil of many nutrients faster than you can replenish them. You need fertilizer to feed your plants.
The agriculture industry as a whole has been battling this same problem for decades, and it is not getting any easier. In the past four decades, soil depletion has led to as much as a 33% decrease in food-grade quality land, i.e, land with good enough quality soil for nutritious foods to be grown.
To combat the effects of soil depletion in your garden, quality compost is a starting point. There’s mulch and leafmould you can add to your soil to add nutrients back into it.
To get fuller, greener and healthier plants and crops though, don’t turn to chemical grade fertilizers. You can make your own fertilizers with products you’re likely to have at home, or find multiple uses for much cheaper, and in many cases, make organic fertilizers.
These are superb DIY fertilizers you can make at home to grow healthier plants that are brighter, fuller, and bigger – and for vegetables with more nutrition too.
9 Easy-to-Make Plant Fertilizers with Everyday (or Easy to Source) Items
1 – Coffee Grounds
Using coffee grounds in your soil isn’t as simple as some green and eco tips you might learn about online would have you believe. You see, used coffee grounds have had some of their acidity reduced to nearly neutral, sometimes lower, other times higher. It depends on the brand.
In most cases, after the coffee has been brewed, the used coffee grounds are pH neutral. However, when you put the grounds into the soil or compost, there’s a different reaction than just fertilizing your plants. That’s because the caffeine left in the coffee grounds can compete for other nutrients when they’re just blanketed on top of soil.
You only need a thin layer and spread sparingly so the grounds don’t compact together.
One of the safest ways to use coffee grounds is to add it to your compost bin with other brown organic matter or to leafmould. This way, it’s not only the coffee grounds, but it’s adding more nitrogen, phosphorous, potassium, and magnesium to the compost you’ll eventually be using in your garden.
If you don’t brew your own coffee, opting to buy from your local coffee store, then that’s where to get used coffee grounds – for free! That’s because, it costs coffee houses more to get rid of used coffee grounds because if it’s not getting used, it goes to landfill.
From there, it emits methane – “a greenhouse gas more harmful than carbon dioxide.” Source: (and further reading: https://blog.epa.gov/2009/02/24/climate-for-action).
So, by using coffee grounds in your compost or adding to your leafmould, you’re playing a part in reducing landfill waste too. That’s a win all-round. Take it!
As mentioned though, be careful with quantities because you don’t want highly acidic coffee grounds to be competing for soil nutrients. That’s why it’s not advised to add it directly to your soil, but rather introduce it to your homemade compost or leafmould.
2 – Grass Clippings
If you have a lawn, the worst thing to do is throw away your grass clippings. They’re a superb source of nitrogen. Additionally, your soil will also benefit from added potassium, phosphorous, chlorophyll, and amino acids.
To make your compost effective, you need to mix green material with brown. Obviously, your grass clippings are the green. It’s nitrogen rich. You then need to balance that with carbon rich material for a good quality DIY compost.
For that, Cornell University has a good table of rich sources for both and guidance notes for using carbon and nitrogen ratios to make quality compost.
The nuts and bolts are – for nitrogen rich sources, there’s grass clippings, the coffee grounds (mentioned above), and vegetable scraps. Manure’s listed too, but chances are, you don’t have that laying around your house. This is about household items you can use as a fertilizer, so…
Getting back to the fertilizer, the way to make this with grass clippings is to make a green tea. Fill a net bag with your grass clippings and place that in a large bucket. Fill with water and leave the clippings to steep. A five-gallon bucket or larger will do the job.
Let the grass clippings soak for a few days. What will happen is the chemicals from the grass clippings will release into the water. You can then use that water to feed your plants, then add the grass clippings to your compost pile. A 2-for-1 on what would otherwise be wasted.
3 – Gelatin as Indoor Plant Fertilizer
Gelatin will only be effective if it’s unflavored. Flavored gelatin has added sugars, which can be damaging to plants.
Unflavored gelatin is used to make low-calorie recipes, and if you have this in your kitchen cupboard, you have packets of nitrogen rich fertilizer ready to go.
Years ago, the Brand ‘Knox’ – a manufacturer of gelatin had a theory that the gelatin could be a rich source of nitrogen for plants. To test their theory, they had the University of Houston test it.
Two years were spent testing 49 species of plants and the study conclusively found that the gelatin does indeed provide a rich source of nitrogen to plants.
Asides from low-calorie recipes, Knox has a web page detailing different uses for gelatin, ranging from plant food to skin care.
Check that out here: http://www.knoxgelatine.com/Gelatine_Bot.htm
The original Knox Gelatine is sold on Amazon.com. There are other manufacturers of unflavored gelatin, however, Knox is the product that’s been tested and proven to be beneficial when used as a fertilizer.
To make a batch of fertilizer, the Knox instructions are:
- To mix 1 pouch of Knox Unflavored Gelatine with 50 ml of cold water in a 1-liter jug
- Leave it for two-minutes
- Add 250 ml of cold water and stir until it dissolves
- Then fill the jug up with cold water and water your plant with the mixture
Plants will only need this once per month and it can be used on both indoor and outdoor plants.
4 – Banana Peels
Banana peels can be a source of up to 42% potassium and up to 25% phosphorous. There’s also the additional calcium, magnesium and sulfur in banana peels, which is why it’s among the best organic material to use to make a homemade fertilizer.
That said, there’s a huge downside and that’s insects. If you just plant banana peels in your soil so it decomposes to release the nutrients, chances are, you’ll attract a bunch of insects.
A more worrying problem is that bees can mistake the scent released as a defense hormone. It’s not a good idea to put banana peels in the soil of household plants.
What is a good idea is to puree the banana peels, or soak the peel in water inside a sealed mason jar for a week, then drain it with a sieve and use that water as fertilizer.
Alternatively, you can bake the peel and then grind it down to mix into your soil. The video below shows you how…
Now, the one thing that banana peels don’t have is nitrogen. To add that into the mix, you can add in…
5 – Egg Shell Fertilizer
Eggshells have a few essential nutrients for plants. Mostly calcium, but they’re also sources of selenium and nitrogen.
You can add eggshells into your mulch, but a faster way to get the same benefits is to crush the eggshells up and boil them.
To make an eggshell brew, you only need a pot large enough to boil a gallon of water and just 30 grams of crushed eggshells.
Boil the crushed eggshells for a few minutes, then leave them in the standing water with the lid on for a few days, then strain.
If you’re using this on outdoor plants, it’d be a good idea to leave the water in a sealed container outdoors to avoid adding too hot of a water temperature to your plants, which could shock them.
6 – Wood Ash
For those with a wood burning stove, there’s a lot of nutrients in the ash. More so if you’re burning hardwood.
Nitrogen and sulfur are lost during the burning process as they’re released as gas. But what’s left in the ash is decent trace amounts of potassium, magnesium and get this… up to 25% calcium carbonate. That’s a good pH balancer there for acidic soil.
Wood ash is only good for your garden when used in moderation. You don’t want a thick layer of this. Just a light sprinkle over the top of the soil and it’ll eventually work its way down, adding the nutrients to your soil.
Point of note: Any soil you plan to grow potatoes with, do not use wood ash. It can cause potato scab.
7 – Cooking Water
Any food you boil, there’s nutrients in the water. Don’t toss it.
Just as you’d use the water from a netted bag of grass clippings as a fertilizer, and eggshell tea for the same, you can do the same with boiled foods. Recycle the water. Drain it into a separate container, let it cool and then water your plants with that.
The nutrients will differ depending on what you’ve boiled. Veggies, rice, eggs, pasta, potatoes and spinach are all examples of foods you can boil and use the water from cooking as fertilizer for your plants, provided you don’t add salt to the water.
8 – Use Vermicomposting for Top-Grade Fertilizer
The most organic fertilizer you can make is compost made from any product that started out from the ground with the help of a red wiggler worm.
These will eat all your vegetable scraps, fruits, paper, cardboard, potatoes (and the potato peelings), rice and coffee grounds. Cotton too.
To get started with vermicomposting, you need a worm bin. You can buy these online, or you can make your own.
You’ll also need the right type of worms. Those are Red Wigglers…
Red wiggler worms will eat half their body weight every day. To know how many red wiggler worms you need, weigh the garbage you throw out that could be used for composting. That will give you an indication of how many red wigglers you’ll need to start.
An interesting thing about this type of worm is they have both male and female organs, so the gender doesn’t matter, they will reproduce. When they do, they’ll eat through more waste, creating your compost faster.
The real gem though is in their poo. Worm excrement is the richest fertilizer you can use on your crops. In agriculture, it’s known as black gold because it can fetch a good price from farmers in need of high-quality fertilizers and this is the most top grade you can get.
To learn more about vermicomposting, some resources include:
- A guide on Vermicomposting
- The Book: Worms Eat My Garbage by Mary Appelhof of Worm Woman Inc > WormWoman.com < Pretty much pioneered vermicomposting for decades
- All about the Red Wiggler Composting Worm
Here’s a video overview of Vermicomposting:
9 – Weed Tea Fertilizer
Weeds are the envy of many a gardener, but they can all be put to a greater use. Think about it… they are living and growing, so they have nutrients there that are suited to the plants you want to grow.
Weeds can be a great source of minerals and microbes that’ll help your crops grow faster, better and healthier.
Making a weed tea fertilizer helps increase your plants’ resistance to diseases and helps deter insects from invading your plants.
The smell isn’t so great though because to make these, you need to leave a bunch of weeds in a bucket of water to ferment for a couple of weeks.
The stench is strong so leave it somewhere in your garden that’s not too close to a window you open for fresh air. You don’t want this smell lingering in your home or near your patio if you’re going to be sitting out having a picnic.
The best way to make a weed tea is to harvest rainwater. If you’re going to use tap water, leave the water out for 24 hours to dechlorinate.
Any weed works for this because if it’s growing, it’s got nutrients. You can extract those by fermenting the weeds. Just be sure to strain the water before using it so you don’t spread weed seeds around your garden. An old sheet or stockings will do the job.
The best type of weeds to use are those with deep roots such as Dock Leaves and Dandelion and those will have more nutrients due to them being deeper in the soil. You can use any weed though.
All you need is a bucket with a lid. Pack the weeds into the container until it’s two thirds full. Then place a brick or large enough rock on top of the pile of weeds to hold them down, then add in your water.
When you put the lid on the container, do not make it airtight because during the fermenting process, carbon dioxide is released.
If that gas isn’t able to escape, it can cause the lid to blow off explosively. Not good if anyone’s near it when that happens so put the lid on the container but don’t make it airtight. Let the gases escape.
Leave the weeds to ferment for a couple of weeks. It’ll need diluted before you use it. A good ratio is 1 part weed tea mixture to ten parts water for outdoor plants. If you’re going to use the weed tea for indoors, dilute it further to take away the smell.
The only plants not to use this mixture on are crops about to be harvested. The taste and smell are likely to be rancid.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.