Spring is just around the corner, and that can only mean one thing, it’s time to start fishing. There are many good places to fish in our area, and some individuals are fortunate enough the either have a pond or have access to a pond.
We are blessed in our area with ponds of many different sizes. Because of the number of ponds in our area our office receives numerous calls about ponds. Probably the most common question we receive is, “When do I fertilize my pond?” This seems like a simple question to answer, but quite often a lot of information is needed to answer this question.
Ponds are complex ecological systems that require close management for productive, plentiful results. Think of your pond more as a garden than a body of water. A pond must be stocked, fertilized, limed and selectively harvested in order for it to be productive. Just as you would fertilize your garden to increase yields, you should fertilize a pond to provide the fish “the crop” with adequate nutrients for growth. A properly fertilized pond can be stocked with twice s many fish as an unfertilized pond.
Before fertilizing a pond, it is important to check water hardness. Water hardness is a check performed to determine the amount of dissolved calcium in the water. Fertilization will not stimulate a good “bloom” if total hardness is below 20 parts per million. I have a test kit to check water hardness in my office. If you need lime in you pond it is best to use agricultural lime (dolomitic). Although lime can be applied at any time, it takes about two months for agricultural lime to go into solution. For best results spread the lime over the entire pond if possible rather than dumping it at one location. Before beginning a fertilization program, you should check the water hardness of your pond. Begin fertilization in February or March when surface water temperatures stabilize above 60 degrees F. Establish a bloom as early as possible to prevent aquatic weed growth.
What exactly does fertilization of a pond actually do? Fertilization increases fish production by increasing the amount of microscopic green plants (phytoplankton) in the water. Phytoplankton is the base of the food chain. The green color characteristic of a fertilized pond is called a bloom, which is due to a large population of phytoplankton. Phytoplankton is eaten by zooplankton which is eaten by insects and small fish. The small fish provide food for larger predators, such as bass. Phytoplankton is also important because they release oxygen through photosynthesis.
What color is your pond?
Spring is just around the corner, and that can only mean one thing — it’s time to start fishing. There are many good places to fish in our area, and some individuals are fortunate enough the either have a pond or have access to a pond.
We are blessed in our area with ponds of many different sizes. Because of the number of ponds in our area our office receives numerous calls about ponds. Probably the most common question we receive is, “When do I fertilize my pond?” This seems like a simple question to answer, but quite often a lot of information is needed to answer this question.
Ponds are complex ecological systems that require close management for productive, plentiful results. Think of your pond more as a garden than a body of water. A pond must be stocked, fertilized, limed, and selectively harvested in order for it to be productive. Just as you would fertilize your garden to increase yields, you should fertilize a pond to provide the fish — “the crop” — with adequate nutrients for growth. A properly fertilized pond can be stocked with twice as many fish as an unfertilized pond.
Before fertilizing a pond, it is important to check water hardness. Water hardness is a check performed to determine the amount of dissolved calcium in the water. Fertilization will not stimulate a good “bloom” if total hardness is below 20 parts per million. I have a test kit to check water hardness in my office. If you need lime in you pond it is best to use agricultural lime (dolomitic). Although lime can be applied at any time, it takes about two months for agricultural lime to go into solution. For best results spread the lime over the entire pond if possible rather than dumping it at one location. Before beginning a fertilization program, you should check the water hardness of your pond. Begin fertilization in February or March when surface water temperatures stabilize above 60 degrees F. Establish a bloom as early as possible to prevent aquatic weed growth.
What exactly does fertilization of a pond actually do? Fertilization increases fish production by increasing the amount of microscopic green plants (phytoplankton) in the water. Phytoplankton is the base of the food chain. The green color characteristic of a fertilized pond is called a bloom, which is due to a large population of phytoplankton. Phytoplankton is eaten by zooplankton which is eaten by insects and small fish. The small fish provide food for larger predators, such as bass. Phytoplankton is also important because they release oxygen through photosynthesis.
Color of a pond can be an important indicator of water quality. Before beginning a fertilization program it is important to understand that a haphazard program is worse than no fertilizer at all.
How often should you fertilize? Usually six to 10 applications per year will work for most ponds. Each pond will differ in the number of fertilizer applications required to maintain a satisfactory bloom. In a properly fertilized pond, visibility should be between 12 and 18 inches. A good rule of thumb is to lower a shiny object attached to a stick into the water, if the object can be seen deeper than 18 inches, apply fertilizer. If the object disappears from view before it reaches 12 inches, the bloom is too heavy and no fertilizer should be added. What type of fertilizer should be used? Use only inorganic fertilizers in ponds. Phosphorus is usually the limiting nutrient in ponds. The percentage of phosphorus in fertilizers is the middle number in the fertilizer formulation. Probably the most commonly used formulation for ponds is (20-20-5) fertilizer. Forty pounds per acre is a standard recommendation. There are many other types of fertilizer available including several types of liquids. Contact your county agent for recommendations.
Not every pond is a good candidate for a fertilization program. If your pond is muddy, infested with weeds, or has high water exchange, you may not want to fertilize. Proper fertilization of ponds is not difficult, but it does require prior planning and good management. As always if you have any question, contact your local county agent.

-Bill Starr is Sumter County coordinator, University of Georgia Cooperative Extension Service. Contact him at 229-924-4476.