Once you have built
your pond, You will need to stock it with plants to
bring it to life. Not only do they beautify it, they also
help to keep the water clear, they also help to oxygenate
it. They also encourage wildlife of all types from dragonflies
to frogs and toads.
The plants full into four
main groups: oxygenators, deep water plants, surface floaters
and marginals. Additionally there are bog plant which
you can put in your bog
garden if you have one.
The recommended way of
planting in ponds for both deep water types and marginals
is to put them in a special pond compost in baskets designed
for planting in ponds, finishing off with a layer of gravel
to stop the compost being washed away. The compost is
not as rich as normal planting compost so doesn't encourage
algae. The baskets have small holes all around so the
planting medium quickly becomes saturated, the conditions
that marginals and deep water plants require. The baskets
stops vigorous plants taking over as well as being easier
than trying to plant in water.
Oxygenators
These are submerged plants. You usually buy them with
a metal staple holding several stalks together. Don't
take the staple off, its weight takes the plants down
and keeps them at the bottom of the pond where they belong.
When you first build and
fill your pond, the water will probably turn a rather
revolting green within a week or two. Don't worry, oxygenating
plants will starve the algae causing the colour change
by competing with them for minerals in the water. It will
soon clear and stay clear as long as you have these kinds
of plants.
In addition to helping
to prevent the growth of algae, if you keep fish, these
plants will also absorb the toxic substances from fish
waste so keeping the fish healthy. The plants provide
food for fish as well as a place to lay their eggs.
Once your oxygenators are
well established, you do need to keep an eye on them because
they can multiply to weedlike proportions. Trim them back
regularly so that they don't take over the pond but make
sure you leave enough to do their job.
Most garden centres that
sell pond plants will have a variety of oxygenators and
will label them as such so you don't need to ask for them
by their botanical names. A few examples are Ceratophyllum
demersum, Hydrocleys parviflora and Preslia
cervina.
Deep Water Plants
These are
the plants that should be planted between 12 and 36 inches
deep and include the best known of all, waterlilies (nymphaea).
As well as being beautiful, their large leaves partially
shade the water from sunlight so helping to prevent algae
growing. If you have fish, the leaves also provide shade
for them. A balance does need to be maintained, though.
The water should not be totally shaded from the sun otherwise
the oxygenators will die, so only about 60% of the pond
surface should be shaded.
Waterlilies
Great care needs to be taken when choosing waterlilies
for your pond. Some qualify as real thugs because they
are so invasive. These types are fine in a huge lake but
can take over a small garden pond and exclude everything
else quite quickly.Another
consideration is that some waterlilies have very big leaves,
in some cases up 18 inches in diameter, again not suitable
for a small pond. When buying your plants, either get
advice from experts at the garden centre or read the labels
very carefully - remember 'vigorous' usually means 'rampant'
and the plant is a complete thug!
Waterlilies should be introduced
to your pond gradually otherwise they might die. Although
they might eventually be planted 36 inches deep, initially
they should only be planted at a depth that allows their
leaves to float. As they settle down and grow, they can
be moved into deeper water - easy to do if they are in
baskets.
Surface Floaters
These also help to provide shade but the same provisos
apply - don't entirely starve your oxygenating plants
of light. Examples of surface floaters are Pistia
Stratiotes, Lemna trisulca, Salvia auriculata and
Wolffia arrhiza. Again, some of these can get
completely out of hand and should not be allowed to cover
the entire surface of the pond. Just drag some of them
out if they start to take over.
Marginals
Along with waterlilies, the marginals are the real stars
of the garden pond show. They are usually planted in a
depth of water between 3 to 6 inches. A few can or need
to go in deeper water so read instructions when planting.
These should also be planted in pond compost in baskets
and put in the pond at the right depth for each type -
depth = from the top of the soil to the water surface.
These are the ones that sit on the shelf you made around
the pond. Put only one variety of marginal in each basket.
Some, like irises, might outgrow their basket and need
to be taken out and divided.
Basic
Planting for Your Pond