Spring: Late Winter or early spring is the time to clean any debris that has accumulated in the pond over the winter. For leaves, blossoms and other organic debris you can use a fine mesh net. In most cases it might be easier to use a pond vacuum. If you have a biological filter and leave the pump running during the winter, you should also clean the filter in late winter or early spring. Don't feed your fish until the water temperature is consistently above 50 for a week (usually about mid-April). Start feeding the fish a spring & fall fish food to start with, and feed only what the fish can eat in 5 to 10 minutes (see koi feeding chart). April is the time to fertilize your water plants (see our handouts on Cultivating Aquatic Plants and Cultivating Hardy Water Lilies).


Summer: This is the time to repot or divide your water plants (see our handouts on Cultivating Aquatic Plants and Cultivating Hardy Water Lilies). Fertilize the water lilies again in July (see Cultivating Hardy Water Lilies). Remove old blossoms and foliage from your water plants on a regular basis and you won't have as much to clean out of your pond in the fall. Water lily aphids can be a problem this time of year. Hose them off the leaves with a spray nozzle or use an aphid spray. Add water to your pond, as necessary. A pond can lose " to 1" of water per day due to evaporation depending on the temperature.


Fall: Start feeding your fish less and switch to a spring & fall fish food around mid-September. Stop feeding your fish when the water temperature drops below 50 (around late October). Clean leaves and other debris from the pond. If you have a lot of deciduous trees and shrubs near your pond, consider putting a net over the pond to catch the leaves. If you have a biological filter, early November is a good time to clean it.


Winter: This is the season to keep your hands out of the cold water, if possible. If your pond ices over, don't break the ice by hitting it. The concussion can harm your fish. You can get an electric pond heater or you can simply fill a gallon milk jug half full of water, put the cap on and place it in the pond. You can then lift the jug by the handle and break the ice without harming the fish. This is not necessary unless the pond is iced over for several weeks. Normally your fish will be fine if you do nothing over the winter, which includes NOT feeding them. Your plants will survive if they are hardy water plants and you placed them at the proper depth (see Cultivating Aquatic Plants). If you have a pump, it will have to be turned off if the ice causes water to spill onto the ground.