Too much water is as
bad as a drought
Too much water can be as
damaging to plants as too little water, says Dammetjies
inventor Geoff Bird.
"That was one of the
reasons I went ahead and designed dammetjies for my own
garden," he said in an interview.
"Only when seeing
the reaction of friends to my dammetjies and after talking
to horticulturalists did I realise there is a great need
among all gardeners.
"Dammetjies allow
you to guage accurately the amount of water to give each
plant, depending on the type of plant, the climate and soil
conditions.
"Dammetjies act as
little storage dams around the base of the plant. It is
easy to remember to fill it up say once a week and know
that amount of water is adequate. Any more water will not
only be a waste, but could actually retard growth or even
damage the root system.
"Dammetjies therefore
also act as water-saving devices, especially as water
goes directly to the roots and not surrounding vegetation,
so keeping to away invaders such as grass or ground covers
that compete for the available water."
He said almost every gardening
publication carried tips on how to plant shrubs and saplings
and also on the importance of proper watering. Common to
all the articles was the need to somehow retain water around
the base of new plants.
Rand Water's Leslie Hoy
and Gail Andrews in a recent article stressed the need to "make
a large basin for watering around the tree while it is establishing
(the first and second year) and water frequently during
this stage."
They advised that "once
the tree is growing well, slowly reduce irrigation to allow
the tree to seek its own water supply. Newly-planted trees
succumb to lack of water, so avoid planting if water is
not freely available."
Hoy and Andrews said the
area around the tree that corresponded to the tree's drip
line should be mulched to a depth of 10cm.
In another article of planting
in dry regions, Louie-Anna Nel advises that once the tree
has been placed in the hole dug for it,"fill the hole
with the remaining soil, leaving ample space for water to
collect during watering. Where the hole is filled with too
much soil, most of the water will run off over the edges
during watering".
Nel said that even when
indigenous trees were planted to save water, gardeners must
be aware that "not all indigenous trees are water wise
plants, and even trees that are drought resistant need regular
watering for the first two years after they have been planted".
In another article, this
time on the planting of ground covers, author Joan Wright
says that "a slight depression around each plant will
help direct water to the root area." She advises that
a light mulch will help prevent weeds from germinating and
also retain moisture.
Bird said all these authors
were in effect telling gardeners to build little dams around
their plants. "That is precisely what our Dammetjies
do. I tried building earth dams around our plants at home,
but the soil invariably washes away and then you have a
back-breaking work of having to build up the walls, before
they wash away again.
"But Dammetjies are
permanent in preventing water from running off. After the
first two years or so when the plants are established, you
can lift them and use them for other new plants. They blend
in with the soil and look neat and tidy.
"Dammetjies are also
ideal for keeping mulch around the base of the plant, as
well as fertilizers," he said.