5
corners – they won’t look
natural and will have a tendency
to collect debris.
Know in advance where you are
going to put the dirt that you
remove. Some suggestions are
to use it for a berm around the
pond, to form an island, or to
create a new garden (perhaps a
raised bed) elsewhere on the
property.
Consider Climate
Find out the anticipated
freezing depth for your area. In
most climates, 2 ft. is
sufficient for small fish and
plants to survive the winter
(but plan on at least 1 ft.
deeper than the usually
thickest ice).
Adequate depth is also
important in warm climates,
since it is dangerous for fish
and plants if the water gets
too hot.
Ledges at various depths
(starting at about 10 in. below
the surface for marginal plants
in pots) are recommended for
different species of plants, with
the shallowest one at least 1 ft.
wide.
Some ponders use sand bags
to form ledges. Many people
choose to add electrical
elements to their pond design,
such as pumps, filters, heaters,
and lights.
The most common filters are
either mechanical (pulling the
water through filter pads) or
biological (passing the water
over cleansing bacteria living in
a contained space).
The details about filters, as
well as different types of
pumps, are available in most
pond construction books. With
anything electrical, you need to
research local regulations, and
be sure that any lines are safely
buried and that everything is
grounded and intended for use
outdoors and around water.
Although you can choose a
shady site, remember that you
will have to remove falling
leaves in the autumn so that
they aren’t sinking and
decomposing in the water or
clogging a filter system. Tree
roots can also puncture liners.
On the other hand, if your
pond is very shallow, shade will
reduce evaporation and
overheating of the water. If you
want to grow a variety of
flowering plants in and around
the water, you will need to be
sure that the site receives at
least five hours of sun per day.
Unless you are designing a
formal pond to be incorporated
into a specific landscape style,
choose a site where the pond
will look natural.
You wouldn’t expect to see a
body of water sitting on the top
slope of a hill in nature, and it
won’t look right in your yard
either.
At the same time, don’t
choose the lowest site on your
property. If it is too low, you
may have problems with
contamination from debris or
pollution from runoff.
Creating a berm, or raised
mound, around the edges of
the pond will help prevent this.
The more level the site, the
easier it will be to correctly dig
the pond.
If there is any slope, be sure
that the low side faces away
from the house or other area
where overflow could cause
problems. If your water supply
is chlorinated or treated with
ammonia, you will have to
neutralize it since these
chemicals can be toxic to
wildlife.
Treatments are available
through companies which sell
fish or water plants. Before
treating, you will need to know
the water capacity of the pond,
which can be determined by
multiplying the length x width x
depth x 7.5 gallons/cubic ft.
Bottoms Up
The bottom of some ponds
consists of packed earth, while
others depend on cement, a
rigid plastic form, or some kind
of flexible liner. If you have clay
soil, digging a depression and
packing down the earth may be
all that you need to do.
If you have soil that drains
rapidly, or you want to be sure
that the soil stays really wet
all the time in order to
support water-loving plants,
then you will need to add a
liner. Other than an earth
bottom, a flexible liner is the
most versatile since it will fit
any shape that you choose to
dig.
– The Rock and Water Garden Expert
Dr. D. G. Hessayon
Pond Ledge
Shelf for marginal plants
