By James Kilkelly
So you find yourself in the middle of the worst drought within
living memory and your garden occupants are starting to sag,
flag and wilt. Which plants should be watered first and which
plants should receive the main quantities of the irrigation? You
begin to feel like the leader of a third world country trying to
spread your counties meagre budget across healthcare, military
and education. Never fear, let me dampen your worries with some
drought advice.
First to receive the H2O
Recent plantings are top of the list for regular watering, if
water is available. New plantings such as bare-root trees or
shrubs planted the previous autumn / winter, with newly planted
perennials also at great risk from drought damage. You see these
new plantings have not had much time to produce water-seeking
roots, the type of roots that travel deep and wide for moisture.
Because of this, we must supplement the plants natural water
supply. During a hosepipe ban, recent plantings of annual
bedding summer bedding such as marigolds, impatiens, Nicotiana
etc should be regarded as probable casualties of the water war.
If I had a limited supply of water to divide between a Japanese
maple and some annual bedding, I am afraid the maple would
receive the lions share and to hell with the bedding. As a rule
of thumb, if the soil 5cm (2 inches) below the grounds surface
is dry, then it is time to water. The following is short list of
plants can cope with a short period of drought, once
established… Brachyglottis, Corokia, Gleditsia, Halimiocistus,
and Hippophae.
Container plants during a drought
Next on the water-receiving list are containerised plants,
hanging baskets and window boxes. Essentially a containerised
plant is growing above the ground water table, with just the
soil inside the container to provide the required moisture. If
the moisture is not inside the container, then I am afraid the
roots have nowhere else to go to quench the plants thirst.
Again, if the compost 5cm (2 inches) below the pots surface is
dry, then it is time to water, it is up to the gardener to
provide that water when required. Try to provide a catch plate
or tray beneath containers, these “catchers” will contain any
excess water that will eventually be absorbed in the compost. Be
aware that terracotta and other porous container materials
absorb a good quantity of water that the plant is then unable to
access. The following is a short list of container bedding
plants that can cope with a short period of drought, once
established… Arctotis, Lantana, Plectranthus, Portulaca and
Zinnia
Vegetables and fruit during a dry spell
Provide adequate quantities of water for moisture-hungry
vegetables such a tomatoes, peas, onions, cucumbers, marrows and
lettuce. Insufficient supplies of water will lead to miniature,
shrivelled and limp specimens. Fruiting plants such as
strawberries, raspberries, currants, apple and pear trees are
also very moisture hungry especially while their fruit is
forming. Notice how much water is within a strawberry or pear
the next time you eat one of these delights. Water-content
figures of 70 to 90% are quoted for fruits and vegetables,
regardless of whichever quantity is correct, you must supply
that water during a drought. Plants growing in an exposed or
wind swept area will require a fair quantity of supplementary
water during a drought. Have you ever gone for a bracing walk on
a windy day, upon arriving home, you smile at your spouse,
children or pet and realise that your lips are cracked and
chapped, ouch! This illustrates the severe drying element of a
strong breeze, plants leaves are constantly being dried out and
then remoistened by water from the soil when available. During a
drought, if that water is not present the leaves will dry up,
shrivel and shed. This is known as the desiccation of foliage.
Watering deeply will prevent this happening.
Shallow rooters and moisture lovers
Shrubs and trees that are shallow rooted or have a particular
liking for moist soils are quite at risk during a drought
period. The shallow rooted specimens include Rhododendron,
Azalea, Heather (Erica), Hydrangea and Birch (Betula). The
moisture lovers include Hosta, Ferns, Helleborus, Sarcococca,
Fatsia and Camellia. If water is available, please allocate some
to these plants. Climbers or wall-shrubs planted close to house
walls will struggle for moisture at the best of times, due
mainly to the rain-shadow cast by the house itself. Do not
forget to water these wall huggers. The following is a short
list of climbers that can cope with a short period of drought,
once established… Clematis Montana, Fallopia, Jasminum,
Trachelospermum and Vitis.
Lawns during a hosepipe ban
During a drought, the first part of the garden that people tend
to water is the lawn. This is probably because lawns usually
make up quite a quantity of most gardens and these lawns tend to
look burnt earlier than many plants. However, the lawn would be
the last form of plant life within my garden that would receive
any rationed water. Lawns are more resilient than you may think,
a green lawn that becomes browned off due to water shortage will
eventually return after a few heavy rain showers. The burnt
piece is the foliage above ground; the roots below ground will
sit tight and wait the dry spell out. Of course, lawns comprised
totally of fine grass will be damaged significantly by prolonged
dry weather, but you should have no worries if your lawn is sown
with a utility seed mix (No. 2 or Manhattan mix).
How to apply water during a drought (if water is available)
I find sprinklers are quite wasteful of the available albeit
rationed water, instead I would choose either hand watering or
seep watering. With hand watering you direct your watering can
or hose to the base of your chosen plant, water deeply at a rate
of approx 10 litres per metre squared. Watering lightly will do
more harm than good as it encourages surface rooting, which is
easily damaged. On many dry soils, water applied directly will
tend to run off over the soils surface and away from the plants
base, if this happens try the following trick. Sink a two-litre
pot filled with gravel at the base of the plant, water slowly
into this pot and you will have no run off problems. Seep
watering, also known as drip irrigation is an effective and
economical way to apply much needed moisture directly. Most well
stocked garden centres will sell seep hose or porous pipe, which
you will weave between plants within your beds and borders. This
seep hose when connected to a water supply will slowly ooze
water through small holes along the length of the pipe. It is
extremely direct and efficient.
About the Author: James Kilkelly runs a professional garden
design service in Galway, Ireland. He has a regular gardening
column in a Irish regional newspaper. Visit his website at
www.gardenplansireland.com/ He also regularly posts his
expert advice on www.gardenstew.com/ Article location:
www.gardenplansireland.com/articles/article17.html
Source: www.isnare.com
