Documents: Special Interest: Water Gardening:

Closing The Pond For Winter
by Carole Reimer
November 24, 1999

Fall has arrived and so have many questions. Unless you are a "die-hard" Canuck, and ya just love Canadian winters and don't mind being cold and wet. ..you will probably be much happier working in your pond during warm weather. Start Fall maintenance as soon as possible... Trust me on this one!

Getting the pond ready for winter can be a very pleasant experience if you follow a few basic rules.

    1st Rule: pick a warm sunny day!.. You're going to be out there for a while.
    2nd Rule: but most important... Please Remember To Never Get Into, Place Any Part Of Your Body Or Work In A Pond Unless All Electricity To Your Pond Is Ground Faulted (G.F.I.) Otherwise, Unplug Pumps, Filters, Lights Etc.. " Electricity And Water Does Not Mix!!!. "
    3rd Rule: Wet pond liners are very slippery.. proceed with caution!!!

First year ponds are usually quite clean so very little has to be done. If you have a build up of sludge and/or dead leaves, this should be removed for the winter, especially if you are over wintering your fish in the pond.

Begin by removing 30% of the water. Pump this water from the deepest area of the pond. After you are finished with Fall maintenance, you will slowly refill the pond with fresh water. Remember to treat if chlorine or chloramine in present in your water. Removing part of the water not only helps with the fall maintenance but also supplies the fish with much needed fresh water over the long winter months.


The simplest and probably cheapest method of removing organic matter is to use a very fine nylon net.... "duct taped" to a pole. This idea came to me many moons ago.. on a very bitter cold, windy fall day. I am short, only 5'0".. and shrinking with age. It was a rotten day and I was chilled to the bone.. I wanted to be doing anything but playing in cold water. I was not a happy camper. I loved my ponds, but on this day, after repeated attempts to reach the debris in the centre of our "smallest pond", this little idea hit and from then on ponding became much simpler in all seasons! Sure ended the cursing and appears to have helped hundreds of other ponders.. short and tall! Of course nowadays, other more sophisticated (and probably more expensive) ideas are out there.

Most frequently asked questions:

    Over Wintering The Plants?

    If you have decided your pond is deep enough that it won't freeze to the bottom, ( two feet in Zone 5) protecting the plants is fairly simple. Most catalogues and/or magazines have a Zone map but of course... read about the zones at ICanGarden!

    Decide whether or not you want to keep any of your Tropical plants. If you plan on over wintering them, they must be removed to a safe warm place before the first frost. If you have fish in your pond you must remove all tropical plants before they die and rot. Floating Plants are full of nutrients so they can be used as mulch or be put in the compost. You can try to keep them indoors over the winter months but this can prove expensive. If you want to give a try, just remember the tropical floaters must be kept in warm water, surrounded by warm air, fertilized and must have approximately 14 hours of sunlight a day. Unless you have your own windmill, you will notice a dramatic increase in your hydro bill.

    Tropical Water Lilies And Other Submerged Tropical Plants, like the Fringes, Snowflakes etc. have to be kept the same manner. Tropical Water Lilies can be "tubered down" but this is time consuming and even the experienced water gardener has loses. Tropical Bog Plants, such as Papyrus, Umbrella Palm, Taros etc. make wonderful house plants. They have to be treated like other house plants Except you cannot allow them to dry out. Just place them by a sunny window in a tray of water. If you "getaway" for a winter vacation, just put these potted plants in a tub of "room" temperature water.


    Hardy (Perennial) Aquatic plants: Hardy (Perennial) Water Lilies and Submerged Plants i.e. Floating Heart. Remove all leaves and place the potted plants in the deepest area of the pond. Bog Plants i.e. Sweetflags, Irises, Water-Forget-Me-Nots, etc. can safely be left on the ledge in most areas of Southern Ontario. In colder areas, place these on the bottom of the pond, but remove all the leaves. Cattails, should be left on the ledge but DO NOT cut off the dead stems until after the new growth is above water level in the spring. Minature and Micro-Minature Cattails over winter in Siberia!

    Snails & Frogs native to Canada usually over winter quite nicely if left in the pond. Again, you must determine your pond is deep enough so as not to freeze solid.

    Fish: Stop feeding your fish once the water temperature reaches 55 Fahrenheit. Common Goldfish, Rosy Reds, Shubunkins,and Comets will over winter outside as long as there is an opening in the ice for the exchange of gases. Oxygen must get in and toxic gases must get out. Leaving a small (475gph) pump running on the ledge will usually suffice, as will an air stone. Do not put the pump or air stone near the bottom as this could cause the pond to freeze solid. We usually recommend 10-14" below the water surface.

    During the coldest of weather, usually February, the pond may freeze over, especially after a January thaw. Cold bitter winds of February, and usually very little snow for insulation may cause a freeze over. The hole can be reopened by placing a pot of Hot water over the area. Some folks use a water trough heater. These 1500 watt heaters are good but expensive to run. We use these heaters occasionally, but only leave them turned on long enough to assist the submersible pump or air stone. We also connect them to a timer. Watch for the new and improved heaters coming on the market. Again, please make sure these units are Ground-Faulted. (G.F.I.). Keep a check on the hydro consumption. No one wants a surprise hydro bill during the most expensive months of the year.

    Japanese Koi & Butterfly Koi require the same as other fish but require deeper water. Even in Southern Ontario, we recommend 4 ft. or more.

    Taking Fish indoors for the winter: This can be a lot of work but also can be very rewarding . You normally have to empty the entire pond in order to catch your beloved fish. It can be fun.. but you have to be warm!. Depending on your pond size, this could take the better part of a day. This is a great opportunity to have a close look at those beauties you have been watching all year.

    Before you empty your pond, you must have a large container waiting indoors. Fifty percent of this container should be filled with aged water and the balance should come from the pond. A heater is not required but lots of air is. If there isn't enough oxygen, you will see your prized fish gasping for air at the surface. If this happens, immediately buy a small $20.00 Aquarium Pump and a 6" air stone. Sometimes you need two or three air stones depending on the quantity of fish you are bringing in. You must also remember that while the fish are indoors, regular 30% water changes are required.

    Assemble pails, large plastic bags, elastic bands and your net. Several fish, depending on their size, can be placed in one bag. Before sealing the bags, we always put a drop of Stress Coat in each bag. Float the bags on the water surface indoors for approximately 1/2 hour. Slowly allow the water from the indoor pond to mix in the bag before releasing the fish. Wait 24 hours before feeding. Do Not over feed your fish. This is easier said then done. Nothing worse than a "begging" fish! In this much smaller container the chances of pollution are high. Your fish could die overnight. We also put a little salt and Stress Coat in the tank before we introduce the fish and again after each partial water change.

    Tropical plants.. treat the same as above. Hardy Lilies. Bog And Other Submerged Plants must be kept, cold, dark and damp with air circulation. Do not seal them in a plastic bag. The best place is usually a Fruit Cellar. The temperature must be cold, just above freezing. The average basement is usually warmer so is not recommended for cold storage. The hardy perennial plants must have a dormancy period. Customers have built inexpensive insulated wooden boxes. These boxes are completely lined with styrofoam sheets and placed in garage or out buildings. Most customer report success. Just keep a watchful eye, if the lilies freeze, they usually die.

    Pumps: All pumps should be thoroughly cleaned and placed in a pail of water for the winter. Do not allow them to freeze or dry out. Fountain heads, filters and filter media should also be cleaned and put indoors.

    Ponds can also be covered for added insulation. Styrofoam sheets, plastic, old unfinished boards, bags of leaves etc. can be used. Just be sure to leave an air space between the surface of the water and the insulating material. Do not lay these materials directly on the water.

    All lined ponds must be kept full of water over the winter months. We do not have experience in Concrete ponds so we cannot advise. Several customers have tried different things but cracks and water loss are a serious problem, especially during the winter months. These customers have now lined their concrete ponds with a liner. We would certainly be interested in hearing success stories about concrete ponds.

    It is very important to remember that just as our water garden will always be different from yours, so may the winter care. Each pond is different. What works for us may not work for you. We have giving suggestions that have worked for us and the majority of our customers from across Canada. As long as you know the winter requirements of the plants and pond life, these suggestions should help you develop a "winter safe" program for your pond.

    Just remember the Perennial plants must have a dormancy, the Tropical plants strive to stay alive as do the fish, frogs, tadpoles and snails. Once you click into this way of thinking, the rest just comes down to common sense and another year of "ponding" under your belt......

If you have specific questions... just ask !

All the best for the "cold" winter ahead. (Burrr!!!)



Happy Water Gardening!!!!!

Specific water gardening problems can be answered by writing lilypad@oxford.net


Carole Reimer,
Reimer WaterscapesĀ®

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