The natural or artificial
removal of
water excesses over and through the
soil.
Drainage is an
essential factor in plant
cultivation.
While all plants
need adequate
water, few will thrive if water congregates around their
roots.
Drainage of land soils:
Drainage is the removal of surface water and/or
ground
water excess from a given area by the use of artificial or
natural means, such that freely moving water can
drain, under gravity, through the soil
by runoff or flow downward to
underground
spaces. Many agricultural soils need drainage to improve
production or to manage water supplies.
The rate of water that moves freely through a soil depends on
soil composition
and
structure, a
compacted soil has poor drainage whereas a
sandy or
gravely soil
(can't be compacted) has rapid drainage. Soils with high
clay
content should be heavily
amended to
provide drainage.
The process of transporting surface water over a land area by
means of ditches to a river,
lake or ocean is called “surface drainage”, while the
removal of water from a soil using drain
(buried pipelines) that are regularly spaced and perforated is
called “subsurface drainage”.
Drainage in pot culture:
The drainage in pot plant culture is very important, if the
pot provides
inadequate drainage, a plant can literally drown in water.
Inadequate drainage also leaves plants
susceptible
to other dangerous conditions, such as
Crown Rot
and Root Rot.
The
excess of moisture in the soil probably indicates that the
pot is not draining properly. If left uncorrected, a pot with
inadequate drainage will almost certainly be
detrimental or
fatal to the
plant.
Insufficient drainage may be
the result of a number of causes:
•
It
may be that the pot has no
drainage holes at
all, or they are simply too small.
•
Alternatively, there may be something obstructing the holes
so that water cannot get out.
The
potting-medium contain an excessive percentage of
organic material that
absorb and hold moisture.
How to provide and improve
adequate drainage and
aeration
in potting soil:
•
The
pot must have one or more adequately large
holes in the
bottom.
•
Make sure the pot is not too large.
•
A
standard practice in
gardening is to line the bottom of the
container with
gravel
and/or broken
pottery (bits of broken flower pots). This permits to
keep the soil in the pot, permitting to cover the hole so
that the soil stays in, but water can drain out and air can
get in.
A means, whether natural or
otherwise, by which water is allowed to flow off a properly as a
pipe through which liquid is carried away.
In horticulture: a drain may be an underground
buried slotted or perforated pipe or other conduit (subsurface
drain) or a ditch (open drain) for carrying off surplus
groundwater or surface water in a drainage system
In Surgery and dendrosurgery: a drain is a
tube inserted into a body cavity (as during surgery) to remove
unwanted liquid material
To draw of a liquid by
something allowing liquid to run out of it by a gradual process or
completely.
Intransitive
To flow off gradually
Drainage basin
Synonyms: Catchment
basin.
The entire area drained by
a river and all its tributaries; a small valley .
The land area that
contributes all of the water to a river or lake system or
directly to the ocean, including tributary rivers, streams,
sloughs, ponds and lakes that contribute to the water supply of
the watershed; also referred to as a catchment basin.
Some species of climbing
plants develop holdfast roots which help to support the vines on
trees, walls, and rocks. By forcing their way into minute pores and
crevices, they hold the plant firmly in place.
Climbing plants, like the poison ivy (Toxicodendron
radicans), Boston ivy (Parthenocissus
tricuspidata), and trumpet creeper (Campsis
radicans), develop holdfast roots which help to
support the vines on trees, walls, and rocks. By forcing their
way into minute pores and crevices, they hold the plant firmly
in place. Usually the Holdfast roots die at the end of the first
season, but in some species they are perennial. In the tropics
some of the large climbing plants have hold-fast roots by which
they attach themselves, and long, cord-like roots that extend
downward through the air and may lengthen and branch for several
years until they strike the soil and become absorbent roots.
Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House,
1994
