For all those who own ponds and live in a four season climate, we now have to talk about the practical way to prepare your pond for winter. In this post, we'll be talking about eight key components of winterizing your pond: the pump, skimmer, UV clarifier, filter, water, fish, plants, and netting. If you address these eight key elements of winterization, you're well on your way to a great spring open!
The image above shows a winter picture of Andra’s pond (see Pond Photos for more pictures of this and other customer’s ponds) that shows off a December light snow. Although the netting in this pond does not demonstrate the "tenting affect" that I prefer because leaves and debris are more likely to blow off of the pond, if removed early in the spring, this net will allow Andra to remove most of the leaves that have settled there.
If you look carefully, this pond DOES demonstrate an open hole in the ice created by the air bubbles from her air pump. With this important exchange of methane from the pond for fresh air, no doubt spring will greet Andra with live and healthy fish in her pond. And they will still be there because the netting will prevent birds of prey from removing them! Andra, thank you for sharing your pond photos.
Eight Ways to Prepare Your Pond for Winter
1. The Pump
There are two schools of thought… one is to leave the pump run all winter. This carries several risks. First, running the pump in freezing temperatures can cause "ice damming". This means that ice could change the flow of your water, directing it out of the pond or off of the waterfall, and it is possible for the pond to be pumped dry. Worst of all, this can happen under a sheet of ice on the top of the pond so that you may not even be aware of it. Secondly, if your electric shuts off or it gets cold enough to freeze moving water your pipes and even the pump itself could be split by swelling ice. Therefore, though there are some risks inherent with taking the pump out of the pond too, I recommend removal of the pump for the winter. Here in Pennsylvania I remove the pump right after Thanksgiving and put it back in by Easter.
Tips for removal and storage of the pump:
- This is the advantage of a discharge kit or union on your tubing at the pump. Then no heating of cold pipes or cutting of pipes is necessary and removal is simple and painless. If you didn’t have a discharge kit on your pump this year, consider buying one from Practical Garden Ponds this winter to install next spring so that from now on your pump placement and removal will be easy.
- Some people store their pump in a bucket of water in the basement or heated garage so that the rubber gaskets etc won’t dry out. This is not something you must do, but it will add longevity to your pump.
2. The Skimmer
In addition to removing the pump from the skimmer, I also remove the basket and filter mat. I throw the filter mat away after a full season of use and start with a fresh clean one in the spring. You do not need to drain the water out of your skimmer and it does not matter at what level you keep your pond for the winter, it will fill up with rain and snow anyway, but as an extra insurance against ice damage inside the skimmer I recommend putting a sealed (capped) empty plastic milk jug inside the skimmer. This way when ice pressure builds up it will simply crush the milk jug.
3. Ultraviolet Clarifier
The UV clarifier must be removed from all ponds that will experience freezing temperatures. The bulbs are fragile and will break if pressed by swelling ice. The unit may also be damaged. Generally I recommend starting fresh each spring with a brand new UV bulb. This will give your pond the best protection. It is possible to wait to change your bulb until you have green water, but it is amazing how many people forget to change the bulb and wonder why their pond now battles with green water even though they own a UV. The best method of pond care is established routines.
4. The Filter
Different filters require different care. If you have an Ultima II or other pressurized filter, you must open the bottom drain valve and empty all of the water to avoid damage from freezing. Non-pressurized bogs, waterfall filters etc. can simply freeze… the ice will move or swell upwards like cubes in an ice-cube tray and do no damage. In the spring you can do any cleaning that is necessary before you start fresh for next year.
5. The Pond
The pond itself will winter quite well. It is strongly recommended that you keep an air hole open on the surface of the pond when the pond freezes over. This will allow methane gas to escape and fresh oxygen to enter. There are many ways to keep this hole open; one is to use an outdoor heavy-duty air pump. The bubbling action from the diffuser will usually keep a hole open in the ice and fresh air will be forced into the pond. Please note that the best placement for this aerator is on one of the shelves in the pond. Placing the air diffuser at the bottom of the pond causes the pond to circulate and will make the water at the bottom of the pond colder! Therefore, it is best to keep the diffuser in the top half of the pond on a shelf or other semi-shallow area.
A second way to keep a hole open in your pond is a deicer. There are many brands and types. The point is not to heat the pond but only to keep an air hole open. Therefore I recommend the floating type. Locate your deicer or air pump over a deep area of the pond where you want the fish to stay. If you would rather put effort instead of money into your pond, it is also reasonable to pour hot water onto the ice each day to open a small air hole. DO NOT under any circumstances use an object to beat, smash or break a hole in the ice. Firstly, this is harmful to the fish, and secondly, it is no fun to repair a hole in the liner in the middle of the winter.
You may consider both an aerator and a deicer since, as with anything else in the pond, redundant systems act as insurance against unexpected equipment failure.
6. The Fish
Although very small or weak fish may not winter over, healthy fish have no problem living through the winter in a pond with good water quality. If you follow the guidelines I have written here, you should have no problems. In addition to the other recommendations on this list, stop feeding your fish when the temperature of the water drops below 50 degrees. You may feed sparingly if you have a week or two of real warm weather even through the winter but remember, keeping the water clean is more important than a meal or two. Never feed your fish at a normal level when your pump and filter are not running but feed only sparingly, if at all.
7. The Plants
There are several categories of pond plants. The care of each is different:
- Tropical Pond Plants: A tropical plant is to the pond what an annual is to the dirt garden. Tropical plants should be taken out of the pond before the first frost and taken to a green house, or thrown away immediately after the first frost damage is noticed. Do not allow the plants to simply die and rot into your pond. This creates unnecessary water quality problems.
- Semi-tropical plants: These plants can winter over in mild climates. Some of them, like Umbrella for example, may be able to be placed in a window in your home in a pot and kept over the winter by keeping the soil wet. Others could be wintered over in a thermal planter (a heated pot that plugs into your outlet and remains in the pond all winter).
- Hardy Water Plants: Hardy plants are to the water garden what perennials are to the typical garden. Hardy plants will die back for the winter but come up again next spring as long as the bulbs, roots or tubers do not get directly exposed to extreme temperatures. When hardy plants begin to die back, cut off the foliage so that it doesn’t rot into the pond. Leave the roots, bulbs or tubers in their pots or in place in your bogs. It is a good idea to move the pots into deeper water for the winter and bring them back to shallow water in the spring. Don’t be quick to throw out these pots in the spring. They can look dead and yet surprise you when the really nice weather hits.
8. Protection from Debris and Predators
Depending where you live, winter can also cause problems with falling leaves and other debris from outside of the pond, polluting the water. In addition, as your plants lose their leaves and your fountains and waterfalls lay still, predators find it easier to spot and catch your prized fish. The solution to these problems may be to put netting over your pond until spring. We sell two qualities of pond netting. Both have fine nets to keep out leaves and needles. The Custom Pond Nets are easy to stretch tight as they have strong edges and can be purchased with tent stakes and bungee cords to keep them taut. Otherwise, creating a tent affect is recommended to prevent leaves from laying on top of the netting and eventually rotting and falling through the net.
Don’t be discouraged… winter will be over before you know it and every spring greets the pond owner with new life, fresh ideas and nature's surprises. To me, winter is a necessary perspective that makes the renewed beauty of the spring pond all the sweeter and carries with it spiritual lessons for life and eternity.