Sproutingfam.com is supported by its readers. If you purchase through a link on my site, I may earn a commission. Learn more
Fermented plant juice (FPJ) is a liquid fertilizer made from local plants and brown sugar.
Korean Natural Farming and most types of Natural Farming practices take advantage of what nature provides. What you have in your local vicinity. Bioliquid fertilizers, like this fermented plant juice fertilizer, do exactly that. This FPJ recipe teaches you how to make this staple KNF input.
Fermented Plant Juice Recipe
The plants or vegetables used to make FPJ contain chlorophyll, plant tissue, hormones, and beneficial microorganisms from the leaves.
The faster it grows, the more beneficial hormones it has. The microbes eat up the brown sugar and kick off the fermentation process.
A single square centimeter of a leaf’s surface contains somewhere around 100,000 to 150,000 cells of microorganisms, most of which are lactic acid and yeast producing.– Applied Natural Farming
If you know how to make any fermented food recipe, then you’ll pick this fermented organic liquid fertilizer recipe right up.
Watch FPJ be made Hawaiian-style
In this video below, a Hawaiian farmer explains how he farms using traditional Korean Natural Farming methods and shares useful information as he makes a fermented plant juice on camera.
When properly made, FPJ contains:
- Beneficial plant hormones
- Primary and secondary plant nutrients
- Lactic acid microorganisms
FPJ is the third of three fermented plant fertilizers we like to use in our home gardening as well as with Ling’s plants she sells at her shop.
To make fermented plant juice fertilizer, you can use any leafy greens, kitchen vegetable scraps or even weeds growing between your driveway cracks. Ideally, you’re using the tips of plants and herbs with morning dew on them. Banana plant stalk works great too. You want to extract the water from these, so you can imagine how nice banana plant is.
For application, you can use it for everything, from seed soaking and soil preparation to support budding plants to general waterings to support overall growth.
Fermented Plant Juice Recipe (FPJ) PDF
- 1 Clay jar
- 1 100% cotton fabric
- 2/3 full Plant material fast growing plants before sunrise
- 1/3 weight of plant material Brown sugar or molasses
- Water *Optional. If needed, just enough to top off the plant material
- It’s important to know that this fermented plant juice should be started right away after gathering your plants. Start the ferment while the plants are still fresh or else you will have a low quality, weak fermented juice.FPJ Step-By-Step Directions: First thing in the morning, go out and pick your green plants as they still have their morning dew
- Do not wash these plant leaves, just swipe off or lightly flick off any dirt or debris. If you wash it, you lose many beneficial microorganisms the FPJ needs .
- Weigh your plant material, then mix in with it 1/3 of its weight, brown sugar. (You can use up to 1/2 of the plant material’s weight of brown sugar, depending on the plant’s natural water content)
- Next, stir these together in a container on a wide tray or container. Lay some newspaper on top and let it sit for a couple hours.
- After the initial waiting period, place the mixture in your clay pot. You should have enough to fill the jar up 2/3 full with the plant and sugar mix. Don’t bring the newspaper into it, just the plants and sugar mix. Leave 1/3 free for air circulation.
- It’s recommended to place a rock on top of your plant material mixture to push out extra air before rubber banding a thin cloth or piece of paper on the clay jar as a lid. If your container has it’s own lid, don’t use it. Use paper or thin cloth (we had a million 100% cotton thin sheets we used for our newborn. These are perfect for fermenting clay pot lids. By tying a cloth or paper tight it keeps little critters like fruit flies out.
- After 1 to 2 days of sitting in a dark room, open the jar and remove the rock you have inside to remove extra air. You can use any heavy object for this, but at this step take it out. Will no longer use it.
- Leave the clay jar open for a few minutes up to an hour and then cover it again to let it ferment for a few more days.
- After around 5 days, check the plant material to see if liquid is coming out from the plants yet. The sugar should have broken down the plant cells and started the decomposition process to get it fermenting. If there is no water yet, at this point you want to add clean water to it yourself, just enough to top off the plant material, no more. Cover it again and place it back in your dark room.
- Next, after adding the water or confirming water has been extracted and covering it again, leave it be for 2 to 3 weeks. Do not touch it, mess with it, check on it, or move it to a better location in these 2 to 3 weeks. Leave it alone to let it complete the fermentation.
- After this final waiting period, it should be finished. The fermentation won’t have a very pleasant smell. It will be sour. If you see tiny bubbles, then it’s well made and ready to use.
- Strain and store: Last step is to strain the plant material out. Discard the solids and keep the liquid fermented plant juice in an air tight container. It will last a year in room temp in an airtight container.
- If the plant leaves are large, cut them into ~10 cm pieces to increase osmotic pressure (plant cell breakdown starts fermentation process) and surface area.
- Make sure to let the FPJ ferment undisturbed. Bubbles start forming after a couple days and this is a clue that all is well. If after a week it’s still not fermenting, your weather may be too cold, or it may be due to disturbing it too much in the first days.
- The finished FPJ will have a light alcohol scent. This is normal for ferments and is caused by chlorophyl breaking down.
- Plants that were washed or collected after a rain won’t have enough lactic acid bacteria or yeast. This will make the ferment come out thick, dark and sludgy. It is still usable, but it’s not a prized possession like a well-made FPJ.
- Choose plants that grow fast. Faster growers contain growth hormone that plants really respond positively to when fertilized with it. They’ll in turn grow faster and stronger as well.
What Happens During Fermentation To Make It A Fertilizer?
FPJ from green plants is rich in nutrients and growth hormone for plants.
In order to become fermented plant juice, the green plants produce cell sap and chlorophyll by using sugars that build up the osmotic pressure that breaks down plant cells and starts the process of decomposition by fermentation of the agents’ cell walls by microorganisms.
Did You Know?
Fermented Plant Juice is edible. Although your FPJ should be non-toxic and safe to ingest, I wouldn’t recommend it if you didn’t use purified drinking water to make it.
How To Use Fermented Plant Juice Fertilizer
The concentration should never exceed 0.2%.
- Early Stages: Use a 0.1% concentration of FPJ for seed soaking, germinating plants and to fertilize your seedlings.
- Mid-Stages: 750:1 Once you see stem growth, increase the concentration to 0.2%.
- Later stages: 500:1 Dilution. Spray onto leaves and fruits. It will take some personal experimentation depending on your local factors and plants used. Potatoes for example, don’t like fermented plant juice fertilizer at all. Most plants do thrive with it though. I find the 500:1 dilution to work better than the stronger 200:1.
Warning: With liquid fertilizer, less is more.
Using too much can kill your plants.
For those with livestock, if any disease is present on your farm, it is recommended to avoid making this as you’ll risk spreading the disease. It would be necessary to use plants they don’t interact with or wait it out.
KNF Liquid Fertilizer Dilution Guide
Before fertilizing your plants with green plant FPJ, you must dilute it.
- 1 part FPJ to 500 parts water (0.2% concentration)
- 1 part FPJ to 1,000 parts water (0.1% concentration)
0.1% (also commonly known as 1:1000 dilution)
For this dilution, use 3/4 tsp per 1 gallon. This scales up to 1 1/4 tbsp FPJ per 5 gallons of water and 3/4 cup FPJ for 50 gallons of water.
0.12 (slightly stronger than the 1:1000 FPJ Solution)
For this dilution, use 1 tsp per gallon, 5 tsp per 5 gallons, 1/2 cup for 25 gallons and so on.
0.2% (1:500 dilution)
This dilution comes out to 1 1/2 tsp FPJ per 1 gallon of water, 2 1/2 Tbsp per 5 gallons of water, 5 Tbsp FPJ liquid per 10 gallons, and so on.
0.5% (1:200 dilution)
This is the strongest I’ve seen recommended, but I have no experience using this strength successfully on our vegetables or herbs. I stick to the 1:1000 and occasionally use the 0.2%.
Some more tips to help you make a perfect green plant FPJ.
- Select the right types of plants. Use plants that are growing in your farm or garden to make the fermented plant juice. These same plants are the best choice for your growing needs because the fertilizer you’ll use is made from the same plant it’s fertilizing. The benefit of this is that you’ll get all the best and vital substances those plants need to grow strong.
- Plants have the most nutrients before sunrise. Early morning fast growers make for the best FPJ plant ingredient. However, you can also use plants on a sunny day.
- The key is to have their moisture levels low. Wait 2 days after a rain to use those leaves for the FPJ. And don’t wash the ones you do collect afterwards before the ferment.
- Choose plants that are growing strong and in season to make your FPJ from.
- Choose plants that have long been established in the local area where the FPJ will be used.
Watch FPJ Being Made
Here I’ll share some great videos I’ve got bookmarked to help spread good information natural fertilizers and farming. This one below is a great one for learning how to make fermented plant juice. He uses the local weeds growing around the farm.
Worth Repeating: Less Is More With KNF Fertilizers
See the dilution guide above.
You must dilute the liquid fertilizer with water. 1 part water to 1,000 parts FPJ is a good starting point for the early germination period and on the seedlings.
As stems develop you can increase the concentration. You still never want to get to 1% as far as I know. The one time I did that I almost killed my resilient chili pepper plants.
KNF FPJ Recipe Summary
I hope this post has been useful in helping you learn all about making fermented plant juice. This KNF fertiliser recipe can easily be made at home with basic materials and ingredients; clay pot or glass jar, cotton cloth, plants and brown sugar, and sometimes water.
Add to that a little time to wait and a space you can keep it in undisturbed and cool, dark and without sunshine, and you’re set to produce a powerful and effective organic fertilizer that goes for a hefty price when buying it from a retailer. The best KNF FPJ will come from your home garden.
You can also use FPJ with your livestock and animals. FPJ residue mixed with feed can increase your animals’ good gut bugs. In pens, it’s mixed in floor material as well as sprayed inside to neutralize odors.
A great blog post by Rooftop Ecology I’ve used as a resource on learning how to make fermented plant juice.
Thanks for visiting Sprouting Fam!
If you have any interesting KNF FPJ information, experiences making it, or tips for us or other fellow food and herb growers who come by to help make it, please let us know in the comments!
Next up: More information on organic liquid fertilizers. Liquid Herb Hormone and Fermented Brown Rice Water are the 2 DIY plant fertilizer types shared in this post.