There are certainly benefits to implementing a fertilization program in your fishing pond. First and foremost: more and bigger fish.
But, as Wes Neal — Associate Extension Professor, Fisheries, with Mississippi State University — points out in a recent article, there are obligations and risks involved with fertilization, as well.
On the plus side:
- Adding nutrients stimulates the growth of the microscopic plants, or algae, that feed the small animals that feed the fish, and these tiny plants can shade the bottom and prevent aquatic weeds from taking over.
Once you start fertilizing, Neal says, you should continue each year because the total weight of fish in the pond will increase, and the fish will come to depend upon the additional food. You will also need to increase your fish harvest to remove surplus production and prevent stunting.
- In short, do not fertilize if your fishing effort and harvest are light.
Also note that fertilization is effective only during warmer temperatures, Neal writes. Start in the spring. Stop when water temperatures fall below 60 F, usually in October. The number of applications will vary depending on the pond’s response. The water should develop a greenish or green-brown color within a week or so.
Neal notes that ponds should not be fertilized if:
- a commercial feed is provided to fish;
- they are muddy;
- weedy;
- have existing dense plankton bloom;
- have a fish population that is out of balance; or
- have excessive water flow.
Before fertilizing a pond, Neal says, it is important to test the alkalinity of the water to see if the pond would benefit from the addition of agricultural limestone. (Alkalinity test kits are typically available at pool and spa stores.) A pond may have enough nutrients to be productive, but the nutrients are not available because alkalinity is too low.
- Adding lime may provide a boost in productivity without fertilization, Neal says. A soil sample will be needed to determine if and how much lime will be required.
- You should also test the hardness of the water, since phosphorus is less soluble in hard water and will require adjustments in fertilization rates.
Neal emphasizes choosing a fertilizer high in phosphorus, as it is the most important nutrient in ponds. Fertilizer comes in three forms: liquid, powdered and granular (which must be kept off the bottom mud until the pellets dissolve).
Again, the bottom line here is: If done properly, fertilization will produce more and bigger fish.
