The main benefit of including humic acids in a liquid foliar application is that the plant will be able to uptake and utilize the nutrients in the solution many times more effectively than without the humates. For this reason, it is an obvious complement to any foliar program.
In the soil, humic and fulvic acids are important chelators, combining minerals into organic compounds that are more available to plants. They also tie up toxins, making them less available to plants.
Humic acids increase the water infiltration and water-holding capacity of the soil. They greatly improve the soil, increase plant root growth and metabolism, enhance seed germination, and help plants deal with environmental stresses. They remove odours in slurry and compost piles, and keep irrigation lines clean. They are often applied with microbial inoculants and liquid organic fertilizers.
They will already be present in good soils with lots of organic matter. Otherwise, they will be lacking and it will be beneficial to bring them in while also focusing on increasing the organic matter content of the soil.
The quality of humic acid products varies widely. This particular humate powder is over 90% soluble and contains a minimum of 80% humic acids.
Using soluble powder is by far the most economical, and even just one pound of it will go a long way. But if you want to try a smaller amount, in a ready to use liquid form, I also offer a 6% humate solution.
Humic Acids Application
The humic acid powder can be applied dry, but it is more commonly mixed with water in a watering can, sprayer, or irrigation system. The liquid humic acids are ready to use after dilution. Although the application rates are very low, they are optimal, so applying more is not better.
Whenever the powder is used in water, pre-mix the desired amount of powder with water in a separate container in order to dissolve it thoroughly before adding it to the final liquid tank. Work slowly, and preferably outdoors - it's messy.
Simple application rules:
Powder: Mix 0.5 to 1 teaspoon of powder into one gallon of water. Soak into soil or spray leaves until wet.
Liquid: Dilute at rates between 1:10 (100mL per L of water) for soil application, and 1:50 (20mL per L) or weaker for foliar spraying. Shake well before diluting.
More detailed instructions:
- To make a 6% solution from powder - Mix the dry powder with water at 77g of powder (90mL or 6 Tbsp or a generous 1/3 cup) per liter of water. Or buy the ready to use liquid.
- For direct soil application, apply 50-100 mL (3.5-7 Tbsp) of this solution per 1,000 sq ft by mixing with enough water to cover the area (between one liter and one gallon for 100mL). For best results, apply at planting or prior to germination and irrigate after. Applications may be made every 6-8 weeks during the growing season.
- For seed treatment, dilute 1:20 (50mL per L). For a transplanting soak, dilute 1:30 (35mL per L).
- For foliar spraying, dilute the solution 1:50 with water (20ml or 4 tsp per 1 liter of water) and spray on plant foliage until the leaves are fully wet. At this dilution, one liter covers some 2000 sq ft. If stains appear, dilute more.
- In daily irrigation systems and for hydroponics, you can dilute down to 1:500 or even 1:1000 (just a few drops per liter).
- Compost Tea - Add 15 ml (1 Tbsp) of dry humic acid powder or about 150mL of the 6% solution into your 5 gallon brewer at the start of the brew. No more.
More application rates