Prepping your water garden for winter


As we have been abruptly reminded by our snow storm in early September, winter is right around the corner here in Colorado.

If you have a water garden, be it a large pond or a small water bowl, you may be wondering what steps you can take to prep them for the chilly months ahead. The following are some tips to keep in mind as you begin your winterizing chores.

Before leaves begin to fall, it is best to place netting above your pond to catch them. This will keep them from accumulating in the water and decomposing — a process that adds both excess nutrients and tannins to your pond water which will cause issues next spring.

For plants grown in ponds, be sure to cut back the foliage to minimize decomposition in the water. Waterlilies can be cut back to the soil line while marginal plants and lotus should be cut to just above the water line. At Denver Botanic Gardens, we normally begin this work in mid-to-late October, depending on the weather. Tropical marginal plants, such as taro and papyrus, can be brought into a greenhouse or brightly-lit room to overwinter. Tropical waterlilies can be searched for tubers that are produced below the soil line. These can be stored in damp peat moss or bags of water and grown out the following season.

If you have fish, it is advised to stop feeding them once the water temperature drops below 50 degrees. As the temperature decreases, so does the metabolism of your fish. Any food fed after this point can either contribute to excess nutrients building up in your pond from uneaten food, or issues with the health of your fish as they struggle to metabolize the food.

Pumps for waterfalls and streams can be left running over the winter months, but be sure to check the area of water flow frequently to ensure that any buildup of ice isn’t causing water to flow outside of your pond’s liner. This can quickly drain your pond, and in turn, burn out your pump.

If you have a water bowl rather than a pond, now is the time to think about where you will store the bowl over the winter months, and how you will winterize the plants and fish. Most water bowls are either ceramic glazed containers without drainage holes or solid plastic tubs. Both styles are susceptible to freezing solid if left filled through the winter. Goldfish can be moved to an aquarium indoors. Plants such as cannas and lotus can be stored in a basement or garage where they won’t freeze. Be sure to check on and water these as needed to ensure they do not dry out completely. Tropical plants can be stored as outlined above.

Tamara Kilbane is a curator of aquatic collections at the Denver Botanic Gardens


Our Papers

Ad blocker detected

We have noticed you are using an ad blocking plugin in your browser.

The revenue we receive from our advertisers helps make this site possible. We request you whitelist our site.