Fish Oil

Fish oil can be added to soil in a couple of different ways. One method is to mix it with water and apply it directly to the soil around the plant. Another method is to mix it with compost or other organic matter before adding it to the soil.
It is also important to note that not all plants will benefit from fish oil. Plants that prefer acidic soil, such as blueberries, may benefit more from fish emulsion, which is a more acidic form of fish fertilizer.