Waking up the Water Garden

The koi scavenge the rocks for algae.

Although it's easily a DIY task, we usually have our local water garden center, Country Gardens,  "open" and "close" our water garden each spring and fall. Spanning just over 22 feet long and 11 feet wide, 5-1/2 feet deep at its deepest point, and with nearly 9,000 gallons of water, our pond is home to nine large koi, a wide variety of bog plants and water lilies, and typically a bullfrog or three or four. It also attracts a regular flock of damselflies and dragonflies each summer.

Our koi hibernate at the bottom of the pond for the winter. A small electric heating element keeps a section of the ice open and a bubbler and air stone provide oxygen exchange in the water to meet the minimal needs of the fish over the winter. The hardiest of plants (reeds, iris, and water mint) remain on the built in plant shelf, 2.5 feet below the surface. The water lilies and other bog plants are dropped to the floor of the pond for the winter. 

The water garden, June 2010

Because our waterfall runs continuously spring through fall courtesy of a pump at the opposite end of the pond, we don't encounter the problem often seen in ponds without pumps: we don't have mosquitoes breeding in the pond. With aggressive spraying in the gardens with garlic and peppermint and the use of a Mosquito Magnet, despite living next to a conservation area, we manage to stay ahead of the mosquitoes most of the time.

In the early spring, once the ice melts, we eagerly watch for the fish to make their way to the surface and begin to school. The pond is usually rich with algae in the spring and that provides plenty of nourishment for the fish until the water - and their bodies - get warm enough for digestion to occur. 

Before the water reaches 50 degrees, these fish don't make digestive enzymes and so they can't digest regular feeding pellets.

Cheerios are quickly scarfed up by hungry koi.

During the early days of spring, if we have an extended warm spell with temperatures into the 50's and 60's, the fish will come to the surface and ask to be fed. Until the water temperature is consistently over 50 degrees F, we toss them a few Cheerios, which are easily digested by their still sluggish GI systems.

Getting the pond running again for the season involves cleaning the pond and restarting the waterfall.  Here's the process, start to finish:

The water is pumped out to our dry river bed with industrial size sumps. Many of the pots of plants are lowered to the bottom of the pond for the winter and those are lifted out to be pruned,.fed, and repotted as needed.

Once the water level is down to about 2 feet, the fish can be easily netted and transferred to a holding tub. They have to keep a large net over the tub as some of the friskier koi will actually jump out of the holding tub.

Steve, one of the water garden techs from Country Gardens, nets one of the koi and passes it to his assistant.

Once the fish are transferred, the remaining water is drained and the stones and walls of the pond are power washed. With Steve standing in front of the waterfall stones, you can appreciate the depth and size of the pond.

There is usually a collection of muck on the floor of the pond - residue from the plants, leaves that settled in the fall, and the occasional twig that blows in - and that has to be removed and hauled to the compost pile. Then the pond is completely drained and cleaned.

After the pond has been cleaned, fresh water is added. pond is refilled and the fish are added back along with a dechlorinator, water conditioner, and stress control drops to ease them through the transition

The water in the holding tank is refreshed with cold water and the temperature is checked against the temperature of the water that is filling the pond. They try to equalize the temperature to avoid shocking the fish when they are returned to the pond.

The koi are transferred back from the holding tank once the water level reaches about 2 feet in depth. It's an amazing time to photograph them.

 Streak, one of our butterfly koi, swims gracefully in about 2-1/2 feet of water after he was transferred back into the pond.

Finally, the plants are arranged on the shelf.  Lifting the heavy pots into the water and arranging them on the shelf is best done from inside the pond.  Steve gets in with a wet suit as the water is still quite chilly this time of year.

This year, we were able to open the pond much earlier than in years past and the plants were all in excellent shape, especially the iris and water mint that had been left on the shelf. The veins of the red dock are a vivid burgundy red and the houttuynia (in the plant in the foreground) is also thick and verdant.

Each spring we take stock and rearrange, repot, and add new plants to our water garden. This year, we added some variegated Siberian Iris and some marsh marigolds which we have been wanting to grow for a couple of years now. We also repotte4d and combined some of the water lilies into much larger pots, and purchased a new lily, Barbara Dobbins, for the end of the pond opposite the waterfall.  Barbara Dobbins  is a pale peach with pink streaks and is reportedly a prolific bloomer, blooming non-stop spring through summer. I'm looking forward to the first blooms from this newest addition to the water garden.  

If you'd like to see the pond and tour the gardens, our garden will be one of the many lovely gardens featured on the Country Gardens annual water garden tour on Saturday, June 25th.  Save the date and check the Country Gardens web site for more information, including maps to all of the gardens on the tour.