After sharing recipes for making your own granular organic fertilizer from inexpensive bulk ingredients, I’ve gotten a number of questions from readers asking how to convert a dry organic fertilizer into a liquid. Why would you want to?
- Liquid fertilizer is fast-acting. A liquid fertilizer can be faster acting than a dry or granular fertilizer, because the fertilizer has already dissolved into the liquid and thus plants will take it up quickly in larger quantities. This isn’t appropriate for all landscape settings, such as when you are fertilizing shrubs, but when you are fertilizing brand-new plants or seedlings, or those plants with an obvious nutrient deficiency such as all over yellowing or yellowing in between the veins, a liquid organic fertilizer can act as an “energy drink” for your plants to give an immediate boost in health.
- It works in cold weather. If you are growing cold tolerant crops and the soil is still below 50°F, a dry or powdered fertilizer will break down very slowly, as the microbial activity in the soil slows during times of cool weather. This is appropriate most of the time, as plants should not be encouraged to grow too quickly when the weather is still chilly, yet when you are establishing vegetable starts or flowering annuals, a little nutrient boost can go a long way towards helping them get going.
- Dogs can’t eat it. Fido and friends think that blood meal, bonemeal, kelp meal, fish meal, and other organic fertilizing agents smell and taste delicious. If you create a liquid organic fertilizer from a granular, your plants will get the nutrients and Fido will be less attracted to dig and snuffle in the garden bed. By contrast, sprinkling out 2 cups of delicious dog-attracting bonemeal can be a recipe for digging, rolling, and eating with some dogs. (More tips for keeping Fido out of the organic fertilizer here.)
How to turn a dry organic fertilizer blend into a liquid
The method is simple. You simply soak your granular organic fertilizer in water, let it sit for 24 hours, and strain out the liquids. This works equally as well for store-bought granular organic fertilizers (like my favorite, Gardner and Bloome!) as it does for homemade fertilizer recipes. Here’s what to do.
- Use 1 cup of fertilizer for each gallon of water.
- Soak the fertilizer in the water, and let it sit for 24 hours. Stir periodically.
- Strain out the solids, and use the liquid as a fertilizer at a rate of 1 to 2 cups per perennial, 2 to 4 cups per shrub, or 6 to 8 cups for trees.
- The liquid can be used full strength for foliar feeding/ spraying on leaves, or can be diluted with a small amount of water to make sure the entire root zone of the plant is evenly covered. For container plantings for example, I would use 1 to 2 cups per gallon and simply soak the entire pot.
- There is no need to waste the solids, which still have nutrient value. Use them as a low powered fertilizer on established landscape plantings which only need a mild boost.
Other liquid fertilizer recipes
Kelp contains a number of healthful growth hormones that are especially useful when growing high-yield plants such as tomatoes, roses, or Humboldt County’s favorite crop, marijuana.
- Take ¼ cup of kelp meal and pour ½ cup of water over it to soak and rehydrate the kelp meal. After a few hours, pour off the excess water (though it’s only a tiny bit, feel free to use it on your plants).
- If you have an old blender, take the hydrated kelp meal and purée it into a kelp meal paste. If not, simply muddle and smash it around with a fork to help release all that kelpy goodness. Then divide it into small portions in an old ice cube tray or Ziploc baggies, preferably in 2 teaspoon increments, and place it in the coldest part of your refrigerator. Label it well so nobody thinks it’s pesto!
- To make a liquid foliar feed, apply 2 teaspoons of kelp meal paste to 1 gallon of water and mix or shake thoroughly. You can then sprinkle or spray on leaves.
- To make a liquid fertilizer to water plants with, use 4 teaspoons of kelp meal paste to 1 gallon of water.
Liquid kelp from seaweed
If you live by the beach, many permaculturists and old-school organic gardeners recommend making your own liquid kelp fertilizer out of fresh sea kelp.
- Add two big handfuls of thoroughly rinsed, chopped sea kelp to a 5 gallon bucket of water and stir a few times a day for three days.
- At the end of the three days, strain and dilute the liquid at a rate of two parts water to one part kelp water.
- The diluted mixture can be applied via a spray bottle, or used to water new seedlings or other plants that may need a boost.
Though making your own liquid fertilizer takes a little more effort than simply sprinkling a dry granular around the soil surface, the immediate benefits from a liquid fertilizer can make it worthwhile in certain circumstances when establishing new plants, caring for high-yield flowers or crops, or even just in keeping Fido from showing so much interest in your newly fertilized plants.
Photo credit: Christopher Craig on Flickr via Creative Commons license
20 responses to “How to Make Liquid Fertilizer from a Granular Organic”
Thank you for the great advice. I don’t have access to kelp but of all the brands I have tried Maxi Crop is the best. We spray it after we finish all our installs. Pinning and saving!
Oh, I have used and loved MaxiCrop in the past as well! Good stuff. And smells very fresh, which doesn’t really matter, but is somehow satisfying.
I thought about using organic fertilizer once, but with my kids’ dogs around I knew it’d be an issue. I had never imagine that organic fertilizer can actually be diluted to make it dog-proof (that’s just how much of a newbie I am). Thank you for the tips!
Gardening with dogs is like gardening with deer – you can make things dog-resistant, but they are never dog-proof! 🙂
Thank you for your tips and advice. My daughter has chickens (not organically raised) but she does have an organic garden. Can she use her chicken poop as fertilizer in her garden and still be organic?
If she eats the chicken eggs, then it makes no sense to be worried about the effect of the manure on vegetables, as the eggs will contain much higher quantities of any pesticide residues.
As for the requirements of organic production for resale, I am not qualified to answer that one.
On kelp and Maxicrop, are you familiar with Edmeades and the Bell-Booth Group Ltd v Attorney-General case in New Zealand?
In a nutshell, Edmeades found in field tests that Maxicrop didn’t do anything. Maxicrop’s manufacturer then sued for monetary losses.
Dr. Chalker-Scott also points out the absurdity of the environmental impact from harvesting kelp to spray on plants when it doesn’t do anything:
Hi, I tried this. I let a granular fertilizer in water for 24hrs then apply to my strawberry plant. It burned my plant. Do you think I should dilute the liquid in water? If yes, what amount of fertilizer (already dissolved in water) with what amount of water? Thanks.
You didn’t mention how much granular fertilizer you used in how much water. However, it is wise to remember that only a few teaspoonfuls of granular fertilizer are placed around a garden planting, pwhich then takes several waterings and several days to be absorbed by the plant.
Use 1 cup of fertilizer for each gallon of water.
Soak the fertilizer in the water, and let it sit for 24 hours. Stir periodically.
Strain out the solids, and use the liquid as a fertilizer at a rate of 1 to 2 cups per perennial, 2 to 4 cups per shrub, or 6 to 8 cups for trees.
The liquid can be used full strength for foliar feeding/ spraying on leaves, or can be diluted with a small amount of water to make sure the entire root zone of the plant is evenly covered. For container plantings for example, I would use 1 to 2 cups per gallon and simply soak the entire pot.
There is no need to waste the solids, which still have nutrient value. Use them as a low powered fertilizer on established landscape plantings which only need a mild boost.
I was wondering what percent N-P-K you suggest for your granular to water ratio of one cup to one gallon. For instance, if you had 19-19-19 would you dilute even further?
If you’re using 16-16-16 granular, one cup per gallon of water is way too much. Three tablespoons would be about the maximum.
Try Kelp4Less. Amazing products!
Your tips are more than helpful. I have a dog, which stays at home in the evening (because it is still a baby) and in the daytime it is playing in the backyard. I have vegetables and my dog is digging around them. One day I read an article regarding how to keep your garden free from pests, but my dog is not a pest, it is my pet so I figured out that to create a liquid organic fertilizer from a granular is a good decision for my problem. Hope it will work, Thank you!
Thank you for sharing! We always have to be conscious about the pets and the children playing in the backyard.
Melissa from Handy Gardeners Ltd.
Thanks for the tips on how to turn a dry organic fertilizer blend into a liquid and making a liquid fertilizer from a granular organic. This is really helpful. I agree that we have to be conscious about the pets and the children playing in the backyard. A great resource!
[…] Granular Fertilizer vs. Liquid Fertilizer So far my 1.5 month experience with fertilizing has been limited to granular organic fertilizers, where I would bury them in soil. With carrots, minimum root disruption is advised and so I think liquid fertilizer would be a better choice. When the time comes, I will be following North Coast Gardening’s guide on How to Make Liquid Fertilizer from a Granular Organic. […]
hi – i found i have a knack for maintaining orchids . i saw a youtube video about orchids that stayed a fertilizer with a high middle number will promote blooms. i have only found this in granular form. can i use the above method of dilution for my orchids and water as i normally do? my orchids grow fine i just want to oomph the bloom growth. thanks for a great website!
I have found Bougainvillas to be a little tricky to grow in Florida, and will only bloom with Bougain fertilizer with the macro nutrients. It advises me to water periodically between feedings with a liquid fertilizer, but it does not tell me what type. Can I make a liquid fertilizer from the Bougain, And what would the ratio be?
I made bokashi compost, is it possible to change it to liquid fertilizer? . I used woodash, rice husks, manure etc