Winter Fish Pond Calendar | Preparing Garden Ponds For Winter
This article relating to preparing garden ponds for winter is predominantly aimed at the Northern hemisphere pond keeper; January for example relates to the Northern Winter month as opposed to the Southern Hemisphere Summer.
If you happen to live in the Southern Hemisphere the seasonal conditions can be treated in a very similar fashion but you will obviously need to change to the appropriate month.
Take a look here...
In the United States, Canada and the UK Winter starts in November and continues until the end of February.
November.
In the UK, normally the season of mellow fruitfulness is over and the feeling and look of a grey blanket settles over everything. A hot summer and a rapid temperature change produces a spectacular autumn display of color. With the on coming cold the pools, ponds and water gardens will have definitely gone to sleep. So if the water has cooled below 7C, don't feed your fish, especially the Koi, and between 7 and 10C only feed your Koi either wheat-germ or some other top quality winter feed.
Many people who have tall grassy plants around the pool and who haven't cut them back are congratulating themselves because there is still cover for the wildlife that is still moving in and out of the pool, unable to settle down, but also it looks very good. In a dry year the likes of Cyperus longus, Sweet Galingale and the indigenous species of Carex or sedges produce quite autumnal blaze. Meanwhile the scented rush, Acorus calamus and its tufty variegated cousin Acorus gramineus stay evergreen.
If you do decide to cut back the undergrowth, cut it right down to water level. Leave the likes of Acorus and the Carex Bowles Golden unless they are looking particularly sorry for themselves.
Now assuming that November does actually come up trumps with some seasonal weather we should be thinking in terms of the normal routine of cleaning out pumps and removing altogether in cold districts and storing away.
If there is a biological filter, the filter pump should be repositioned onto the marginal shelf so that just the top few inches of water are being turned over, rather mixing up the whole lot. As water gets to around 4C, it becomes its most dense and sinks to the bottom of the pool.
Fish are quite content to live down in this water that is oxygen rich. If the water were to get any colder it would rise up in the pool (contrary to any physical behavior of any other liquid or even water at higher temperatures) and as it approached the magical 0C it would turn into the solid that we know as ice.
This naturally enough is not to fishes liking. So, if we are turning over the whole volume of the pool through a filter or waterfall and the cool extremes at the surface, we would find the whole system cooling down like refrigerator, down to the temperatures at the surface. So try to keep the lower reaches of the pool undisturbed.
As things get colder, the biological filter is operating less and less on a biological level. If conditions freeze then the filter needs to be stopped. When things warm up, and you turn the filter back on, it will be like a two slug Russian Roulette as to whether it will or will not deposit toxic filth into the pond, at a time when it least can cope.
So the best bet here is to clean it out now. Clean out the filth in the bottom with rain or pool water and rinse out the sponges and the filter medium. If you have an ultra violet clarifier that is easily detached, bring that in or make sure it is empty of water.
If the pool does ice over, don't break the ice with a hammer. This knocks the fish senseless. Two or three days ice wont do the fish any harm. If however there is a lot of muck in the bottom of the pool and there may be a build up of noxious gases in this time, sit a pan of hot water on top of surface until it melts a nice hole.
This will enable any build up of gas to be released. It will also relieve the stress the ice may be causing on the fabric of the pool liner or its structure. If you are after something more aesthetically pleasing or more automated then try a de-icer or fish pond heater.
If it does get really cold, take Lobelia cardinalis under cover. By the way, if youve invested in any slightly exotic plants like Cannas or floaters like Eichornia crassipes Water Hyacinth (for those of you in the US and SA- yep! They actually grow them on purpose in the UK.) and Pistia stratiotes, Water Lettuce, take them into a frost free greenhouse and grow them in a tray. Water Hyacinth can actually be planted up in a pot to make it more winter hardy.
Plants flowering at this time of year? The hardy South African Aponogeton distachyos- the water hawthorn, and in the bog the other plant from around there, Schizostylis coccinea, once commonly referred to as the Kaffir Lily, now it is considered more politically correct to refer to it as the River Lily. It is a fantastic show at any time of year, let alone blazing away in the dull washed-out blear of the sad grey English garden in winter.
Keep warm and dry.
DECEMBER/JANUARY
What needs to be done with the water garden? Nothing. It is asleep. What has been done that needs to be done can now wait. As long as it is cold enough and the water is below 5C, everything in it is blissfully unaware of everything, so don't disturb it.
After all you hate to be disturbed during your slumbers. Instead, appreciate the garden in its winter dress. Get into the Christmas spirit and brighten your house and the faces of your friends and neighbors with a few of the indoor plants that we have come to associate with this time of year.
JOBS LEFT UNDONE MAY BE A BONUS
In the first two or three years after planting, the more grassy marginals, particularly the Carex and Cyperus still look good in early winter. As everything else dies back to ground level, the clumpy grasses move in the wind, lending animation to an otherwise static scene.
The other tall marginal plants that you have failed to cut back may pay unexpected dividends if we get any hard frosts. Fronds of all herbaceous plants and some shrubs look stunning in winter sunlight covered in an icy hoar.
What is more, even the most humble reed that has run to seed will provide excellent emergency rations for small birds and will help provide cover for any wildlife that needs a mid-sleep sip of water.
You may be able to use some of these seed heads in a dry plant display. A vogue that is set to return in force now people are beginning to forget the amount of dust that dried plants seem to attract.
The reed mace (Typha angustifolia) and even the Norfolk Reed (Phragmites australis) can be put to ornamental use. But beware they can be as much as a time bomb indoors as out, because at a certain times of dryness and humidity they can just deposit their seed head like an exploding dumper truck.
Also impress upon any resident cats that a reed mace (bulrush) frond is not their Christmas present. To them it looks like a cross between a barbequed anorexic mole and a mouse kebab and definitely something to be torn apart, purely for scientific research of course!
CONSERVATORY OWNERS PLEASED
If you were one of those people that decided to build a conservatory over your water garden as a result of being lured into the delights of exotic water garden plants then things are possibly still up and running. There is a limit to how much heat you can afford to pump into these things and you may have opted to settling for it to be just a frost-free zone and have let things wind down for the winter.
Even so if you have been growing the fascinating Nelumbo or Lotus water lilies you may had some flower. If there were any remaining seed heads you may want to dry them. They make a fascinating focal point in any dried flower arrangement.
ALL TIDIED UP AND BATTENED DOWN FOR WINTER?
Pond-wise, if you are cleaned out, dredged up, cut back and neatly netted for winter, now is the time you can appreciate another role the water garden can play in your garden, and that is as a source of light and reflection. A backdrop helps or alternatively a view to the horizon with a frame set by plants or landscaping ornaments set either side.
If you have good structure to the landscaping in your garden it becomes most apparent now, whether it is a formal or informal. So if there is no fear of herons, remove the net once all the leaves have fallen to reveal the unexploited qualities of your water garden.
If it snows and settles on an icy pond, brush as much off as you can to let some light down into the pool and remember don't break the ice. Melt it with a pan of hot water sitting on the surface.
Or switch on a pond heater to maintain a hole in the ice for gaseous exchange. Either way, melt it don't break it. This is particularly important for koi and or any birds that might appreciate a drink, especially ducks.
FEBRUARY
Here in the dismal UK the sun has begun to shine but it comes with cold air from the north and a thick layer of ice is back on all the ponds. You would think the little world that seemed so active during the summer months was completely dormant. Not so, I was reminded of that three times this week.
First of all, one of the local district councils has put up its road signs warning of Toads Crossing. Suddenly, I realized that its the time of year those little amphibious monsters crawl out of their leaf heaps to get it on. One of the gardeners best friends, they migrate in startling numbers to the place they developed as tadpoles to miniature toads.
Females are always in short supply, so the adult males will attempt to mate with anything that moves including docile fish or another pair of mating toads. Sometimes there can be more than a dozen of males in a rolling ball in the pool - somewhere in the middle is a suffocating female. It is not surprising that the collective term for toads is A BUNDLE TOADS.
Although the water in the pool has stayed pretty much below 10C or 50F you might think that might be another reason for nothing going on. In fact that is warm enough for the blanket weed or Spirogyra to take advantage of the lack of competition.
An old client of mine with a wildlife pond was inundated with this green cotton woolly thread form of algae. He has no filtration or even moving water and his pool is surrounded by chalky limestone that produces very hard water in the pool, and blanket weed just loves that. His only resort is to keep hooking it out with a lawn rake until the spring, when the rest of the pool plants kick into activity. The rest of the higher plant life will then prevent the blanket weed from getting a look in on the resources.
Even if you have of the resources of modern technology at your disposal, filters, chemical, U/V clarifiers and magnets on the water supply to the filter, once you have blanket weed it seems like you have got it for life. It does have its advantages if you can keep it under control, because it is always a ready vitamin rich snack for any of the vegetarians in the pool, especially the fish, and if you've got it, you will rarely get any other form of algae or if you do, then there is something seriously wrong in that environment.
Having said that there are some excellent products on the market that do remove the compounds in the water that help algae, and particular blanket weed, to thrive. One such product is called Viresco ... It really is a great cure for blanket weed and string algae.
The Marsh Marigold, Caltha palustris is resolutely pushing its way up. Whether it is a rock hard frozen bog area or sitting with its neck through an inch of ice in the margins, it is determined it going to get out and about before the rest of the mayhem starts in the water garden. In fact its new growth for the following season starts in October when everything else is dying down, and despite or the trials of winter, its little fleshy stems still manage to produce a golden display right at the beginning of spring at the end of March.
The weather is usually still pretty dire then, so it is no wonder this has always been such a popular plant in this country, its bonny display encourages wishful thinking about warm balmy summers.
SEASONAL TIPS:
- If you do have a filter in operation, make sure the pump is only turning over the surface water of the pool. Put the pump on the marginal shelf.
- Keep it going until the temperature drops to 1 or 2C. Then turn the pumps off.
- If the water freezes, don't be too worried for a couple days unless the pool is really dirty or overpopulated with fish. Rotting organic matter in the bottom of the pool will produce toxic gases that if they are trapped under the ice will poison the water. If this is the case melt a hole in the ice with hot water poured into a saucepan sitting on the ice. A hole in the ice will allow gaseous exchange. Never smash a hole in the ice. Unfortunately this is a favorite pastime for kids, especially other peoples. Ah well, Ill let you deal with that.
- If you haven't already done so, clear up dead leaves especially in the bottom of the pool before all amphibians start to spawn. Leave the detritus on the side of the pool for the sleepy beasties you've dredged up to make their way back home again.
- Cut back, the marginal plants, trim the planting baskets from excessive growth. If all the growth seems on the outside and nothing in the basket, get ready to replant next month.
- Look out for Herons, they've got their eyes on your pool. Plastic herons wont deter them at this time of year. In fact they may do the opposite. Get out there yourself and mount an irregular patrol.
- All right?
article supplied by Peter J May

