I avoid picking up synthetic fertilizers whenever I can. Not only am I spending money I don’t need to, but they kill off beneficial microorganisms, don’t last very long, and have harmful environmental impacts.
Synthetic nitrogen is one of the top causes of climate change, on par with CO2 emissions. So, I make my own from organic material for a healthier, cheaper, and more environmentally friendly vegetable garden.
It’s easy and gives you better use for your kitchen scraps and weeds. Plus, you can still make a quick-release fertilizer using compost teas.
(If you want to learn more, I’ve also written a guide to the differences between synthetic and organic fertilizers.)
If you’re looking for a sure-fire, laboratory-tested fertilizer recipe, this one’s for you.
Developed by environmental sciences doctor Will Binton, this recipe uses dried chicken manure, seaweed, fresh grass clippings, and diluted urine. High in nitrogen, this fertilizer recipe will give your garden a quick start in early spring.
Banana peels contain 42% potassium (as well as calcium, manganese, and other micronutrients), and you can capture that potassium for your garden.
Either throw your banana peels in the compost (wash the peels first if they’re not organic to remove any pesticide residue) or make this concentrated fertilizer tea to add directly to your potassium-loving plants.
Compost tea dilutes the nutrients, but your plants will get a quick hit of nutrients that even household and container plants can absorb since it’s liquid.
If you don’t have comfrey growing in your garden, find some. Comfrey is amazing for fertilizer, as its deep roots bring up nutrients from deep within the soil, which are then concentrated in the leaves.
Use this recipe to make a tea that you can either apply directly to the soil or add to your compost pile to give it an extra boost.
Finally, a way to use up all those chicken bones! Bones are an excellent phosphorus source, which your plants need for photosynthesis, flowering, and fruiting.
If you’re a meat-eater, save your chicken bones and grind them to make a homemade bone meal. (Wear a mask when grinding and handling dry bone meal. You don’t want to breathe it in.)
Are weeds getting you down? Robin Sweetser has a fertilizer tea recipe that will make you eagerly awaiting weeds.
Weeds are simply plants growing where we don’t want them to, but they’re often excellent sources of micronutrients for both humans and plants.
If all you have in your backyard is grass, don’t fret. You can still make nitrogen-boosting tea from grass clippings.
Like comfrey, stinging nettle’s deep roots help bring up a ton of nutrients stored in the leaves.
Just make sure to wear thick gardening gloves when handling, as the “stinging” part of its name is all too accurate.
If you live by the sea, seaweed is a fantastic garden fertilizer that washes up onshore. Check your local regulations, though, as it’s illegal to forage seaweed in certain regions.
Seaweed contains trace amounts of all the micronutrients and contains useful amounts of iodine, copper, manganese, potassium, phosphorus, iron, and zinc.
Make sure you rinse thoroughly to remove any salt. (When using as an overwinter mulch/compost, the rain will carry away the salt.)
Fish emulsion is high in nitrogen, and when diluted, makes a great liquid fertilizer for your lawn. But unless you only need to fertilize a few houseplants, fish emulsion is pretty pricey per square foot.
You can easily DIY fish emulsion using cheap or free discards like fish heads and guts. Just make sure you have a dedicated 5-gallon pail. You will not want to use it for anything else.
The banana peel fertilizer recipe above is great if you’re going to use it right away, but what if you want a little something just in case?
This banana peel fertilizer recipe uses dried banana peels and will last a couple of months.
Vermicompost, also known as worm castings, is fluffy, filled with microbes, and a great way to reuse kitchen scraps without a compost pile.
Buying vermicompost can be pretty expensive per gallon, but with this homemade vermicompost bin, you can make your worm castings for years for only $21.
Leaf mold is essentially composting dried leaves. You don’t even need a yard to do it — just go to the park in autumn and scoop up leaves into a garbage bag.
Leaf mold doesn’t have many nutrients, but it will improve the structure of your soil. You can also add other organic materials like alfalfa meals to provide more nutrients.
Instead of pouring dirty aquarium water down the drain, use it on your plants. The water is rich in nitrogen, potassium, phosphorus, and other micronutrients, all things that plants love.
Just make sure you only use fresh-water, as your plants might not be so happy about getting drenched with saltwater.
If you love sitting by your lit fireplace or have a backyard pit, this fertilizer recipe is for you. Wood ash contains calcium, magnesium, potassium, and other nutrients.
The exact ratios depend on the species of wood burned. Wood ash can be tricky, as it alkalinizes your soil, so don’t apply on acid-loving plants or if your soil pH is above 6.5.
Only apply a little at a time, less than 10 – 15 pounds for 1,000 sq ft for lawns and 20 pounds for gardens. This recipe combines wood ash with kelp meal and sugar for added nutrition.
Bokashi bran is not a fertilizer, but the critical ingredient for bokashi, fermenting kitchen scraps (including meat!) into fertilizer.
And while you can buy the bokashi carbon ratios online, you can also make your own.
And to round out this list, you can make a simple compost in your backyard. You can either use the compost as a base for other fertilizer recipes or use it as a mulch that also fertilizes.
While starting your first compost pile can be confusing with the different ratios of carbon to nitrogen sources, Garden Therapy has a recipe that makes backyard composting straightforward.
See, organic fertilizer doesn’t need to be complicated or expensive. You can use the weeds in your backyard to make a nutritious snack for your garden. Little by little, we can make the earth a bit healthier.
Which fertilizer recipe are you going to try? Let me know in the comments.