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.
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.
They 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.
The quality of humic acid products varies widely. This particular humate powder is over 90% soluble and contains a minimum of 80% humic acids.
This humic acid powder can be applied dry, but it is more commonly mixed with water in a watering can, sprayer, or irrigation system. Although the application rate is very low, it is optimal, so applying more is not better.
Whenever it is used in water, thoroughly pre-mix the desired amount of powder with water in a separate container in order to dissolve the powder before adding it to the final liquid tank. Work slowly, and preferably outdoors - it's messy.
Simple rule-of-thumb application: Mix 0.5 to 1 teaspoon of powder into one gallon of water. Soak into soil or spray leaves till wet. If stains appear, dilute more.
More detailed application rates: