|Autum/ Winter Care
Fall is a significant event for every pond or water garden, especially when
leaves begin to fall from the trees above. If these leaves get in the pond and
decay it could disrupt the ecological balance of a water garden. One option
is to use a net and skim the leaves off the surface. Unfortunately, this can be
a daily chore. Also, don't expect a skimmer type filter to get the leaves.
Skimmers are designed to get the occasional leaf or other floating debris.
Heavy leaf fall can clog a skimmer several times a day. Installing a Pond
Cover over the pond will be easier to maintain.
It is best to try to minimize the amount of accumulated sludge and decaying
plant debris from the water. This can be done with a net to keep the debris
from entering the pond and adding the additional sludge eating bacteria like
Ponds Plus Biological Clarifier.
As the water temperature drops, we should be feeding our fish less as their
metabolism slows down. Hopefully you have been feeding your fish well with
a high protein food, , this summer to allow them to build up a reserve of fat
to help them through the winter. After the water temperature drops to the
sixties, you should decrease the amount of food given and feed only once a
day. Provide food with a protein content of 25 to 32 percent. A wheat germ
based food is good at this time as it is easily digested. Winners Choice
Gourmet Koi Food is an excellent food at this time of year. It is Formulated
with a unique blend of amino acids and minerals to help supplement the
dietary requirements of koi and goldfish in cool water.
As the water temperatures continue to drop to below 60 degrees you should
feed only two or three times a week. It can take your fish two or three days to
digest food at this temperature.
Once the temperature drops below 50 degrees you should stop feeding
altogether until spring when the water temperature remains above 50.
As organics decompose in the pond they can produce toxic gases that
could be trapped in the pond if it is covered by ice for more than a few days.
It is important to keep at least a small area free of ice so that these gases
can escape. Do not break the ice as the shock waves created can damage
or kill your fish. One of the easiest ways to do this is with a floating pond
de-icer or an aggressive aerator. This device floats in the pond and has a
built in thermostat to turn the heating element on when the water
temperature drops below 40 degrees. They can also be used to keep a
small pond from freezing solid allowing you to keep your fish alive.
With their slower metabolism and the absence of plants our fish are more
susceptible to predation by raccoons, birds and other animals. If you took
our advice and added leaf netting to keep the leaves out of your pond this
should protect your fish as well. A Koi Kastle will help your fish be more
comfortable by providing a place for them to hide.
You should have stopped feeding your plants by now. As the foliage on your
hardy plants begins to die back you should remove any dead and dying
leaves and place the plant deep enough in the pond to keep the roots from
freezing. While it is true that some marginal plants will survive even if their
roots freeze solid it is best to lower all of your plants below the ice zone.
A basement can provide protection if you remove the plants and store them
either in their original containers or in peat moss. A method that I like is to
build a temporary shelter over the pond. Lumber or PVC pipe can be used
to construct a framework over the pond. Place clear plastic over this and
weight the plastic down with soil or stone. This frame should hold the plastic
a few feet above the water. Greenhouse type plastic is best but construction
grade plastic should last the winter. This method works very well and is
basically like moving the pond to one USDA hardiness zone higher. On
clear days the sun warms the water and even if covered with snow there is
good insulation over the pond. Some tropicals can be wintered over this
way in mild winters even if you live in zone 6 or 7.
Some plants do not like being submerged in the pond through the winter. Iris
ensata formerly know as Iris kaempferi a Japanese Iris should be removed
from the pond and planted in the yard until spring when new growth starts
and it can be placed back in the pond for the summer. Lobelia cardinalis
(Cardinal Flower) should be removed from the pond and planted in the yard
for the winter. This plant should have a few inches of mulch over it as well.
You will have more success wintering over Cannas if you remove the
rhizomes from the pot and store in slightly damp peat in a basement or
other cool area. Some tropical water lilies will bloom all winter if kept in a
tub container inside and given at least six hours of bright light. You can also
winter them over by removing the tuber from the pot after the foliage has
died back from a freeze. Place the tuber in a container of slightly damp
sand or peat moss at 50 degrees. In the spring you will need to heat the
tuber in an aquarium to about 75 degrees to trigger its growth before
One choice with tropical plants is simply to dispose of them after freezing
weather and replace them in the spring. This way you get to try new plants
and colors next season. If you want to try wintering over your tropical plants
there are a few methods worth trying.
Many tropical plants can be brought inside and treated as a houseplant for
the winter. Umbrella Palm, Taros, and Calla Lilies will do very well with
medium light levels. If these are in no-hole containers then no special care is
needed otherwise keeping the pots in a tray full of water is needed to keep
the plants wet. Water hyacinths and water lettuce require more care than
they are worth; it is much easier and less expensive to replace them each
spring. If you still want to make the effort they require 10 hours of intense
light and temperatures above 70 degrees.
Pumps and Filters
Depending on your climate and other factors you may or may not want to run
your pump and filter system through the winter. If you live in a climate with
temperatures mostly well above freezing then it will be to your advantage to
keep your pump and filter running through the winter. The bacteria in your
biological filter will not be active at low temperatures but it will remain alive
as long as you keep it supplied with oxygen-laden water. When spring
arrives and the water temperature is rising the bacteria can start to work
immediately keeping the water quality good for your fish and helping to
control the algae. Should you choose to run your filter through the winter it is
a good idea to minimize the water circulation in order to take advantage of
the layering effect of the water. (Water temperature is densest at 39
degrees and the water on the bottom of the pond will remain at this
temperature even with freezing temperatures on the surface.) Some ways to
minimize circulation is to turn off bottom drains if possible, place intakes to
pumps/filters at mid-water, turn off surface skimmers, (you do not want to
circulate top or bottom water in the winter), place your intakes closer to the
outlets in the pond (waterfall or fountain), and or turn the pump down. These
actions will allow the biological filters to stay alive without interfering with the
layering of the water. Massive circulation of water in the winter can super
chill the water by exposing warmer pond water to below freezing
temperatures leading to the death of the fish. One problem with running a
pump and filter in the winter is the potential of major damage to your filter
and plumbing system if the power goes off for extended periods and you
are not at home to make sure that no water is present in the filter and
plumbing. If water is allowed to freeze in plumbing, UV's and filters this can
lead to breakage requiring replacement of these units. If your system is
designed to allow the water to flow back into the pond in the event of a
power outage then these problems can be averted. If you have a check
valve installed in your system you can use a long piece of small tubing or
wire to hold the valve open to allow the water to drain out.
You can turn off the pumps and filters for the winter. Cold water holds much
more oxygen than warm water and the fish's respiration is slow therefore
you should not need the circulation and aeration. The bacteria in your
biological filter does not work in cold temperatures so the only reason to run
the filter is to keep the bacteria alive. If you turn off the pump and filter for the
winter be sure to drain all plumbing. External filters, UV's, and external
pumps will need to be drained. Submersible pumps should be left in the
pond or in a bucket of water in a warm place to keep the seals from drying
out. If you choose this method be sure to clean the filter before starting up in
the spring. With the absence of biological filtration you may want to add
Biologinal Clarifier Liquid which contains bacteria that will work in near
freezing temperatures and it also contains enzymes that consume cellulose
in the form of leaves.
A check list for Autumn/Winter pond care
Before the leaves begin to fall, cover your pond with one of several sizes of
leaf netting. (It is much easier to keep the leaves out than to remove them
after they fall into the pond)
This is a good time to divide some types of aquatic plants (waterlilies and
Remove tropicals from the pond as they will decay and pollute the water.
After your hardy plants have stopped growing, cut back the foliage and
lower the pot to the bottom of the pond.
Stop feeding your fish after the water temperature has dropped to the mid to
Also when the water temperature has dropped into the forties, reduce the
circulation of the pond water by either turning off the pump for the winter and
draining of all the plumbing or preferably by placing the pump or the intake
to the pump closer to the water outlet (waterfall etc.) and pick up water from
mid-level of the pond. Also turn down the water flow. Keeping the water
flowing through your biological filter allows the bacteria to live therefore
giving good water quality early in the spring.
If you keep your filter running through the winter, you must take precautions
against the freezing of water in your plumbing should there be a power
You can add a floating de-icer or aerator to keep an area free of ice. This
opening is necessary during periods of ice cover to allow an exchange of