Page 101 - GRIHA Manual Volume II - Introduction to National Rating System
P. 101
Sustainable site planning 93
Lawns
Most lawns receive twice as much water as they require for a healthy growth and appearance. The
key to watering lawns is to apply the water infrequently, yet thoroughly. This creates a deep, well
rooted lawn that efficiently uses water stored in the soil.
Trees and shrubs
All trees and shrubs need more frequent watering from planting time until becoming well rooted,
which may take two growing seasons. Once established, plants can then be weaned to tolerate
less frequent watering. Proper weaning develops deep roots and makes the plants more drought
enduring.
As with lawns, water established trees, shrubs and groundcovers infrequently, yet thoroughly.
In the absence of rain, most trees and shrubs benefit from a once-a-month thorough watering
during the growing season. Remember, normal lawn watering is not a substitute for thorough tree
and shrub watering.
The feeding root system of a tree or shrub is located within the top 30 cm of the soil and at the
‘dripline’ of the plant. The dripline is the area directly below the outermost reaches of the branches.
Apply water and fertilizer just inside and a little beyond the dripline, not at the trunk. Simply lay a
slowly running hose on the ground and move it around the dripline as each area becomes saturated
to a depth of 20 to 25 cm. For large trees, this watering technique may take several hours.
Eficient irrigation systems
The aim of any irrigation system is to give plants sufficient amount of water without wastage.
By zoning an irrigation system, grass areas can be watered separately and more frequently than
groundcovers, shrubs and trees. First, plants with similar water needs should be grouped. Water-
thrifty plants should be placed together and should be separated from grass and plants that depend
heavily on irrigation. The irrigation system should be designed after this. For example, properly
maintained sprinklers are effective for lawns while soaker hoses may be used to irrigate ground
covers. Irrigation schedule should not be rigid and should consider the rainfall pattern. Watering
should be done properly but not frequently. Rain sensors can be installed on automatic irrigation
system to prevent unnecessary watering when it rains.
Both sprinkler and drip irrigation can be incorporated to achieve water conservation in the
landscape.
There are two types of irrigation systems for use in landscapes—sprinkler irrigation and drip
irrigation. Within a water-efficient landscape, a combination of these two systems should be used
for watering lawns, trees, shrubs, groundcovers and flowers. Overall irrigation requirements will
vary according to plant species, soil type, rainfall, and temperature. Established, well adapted plants
require less frequent watering than newly planted trees and shrubs.
Sprinkler irrigation
Sprinkler irrigation is the most commonly used method of landscape watering. The two most
common types of sprinkler irrigation systems are the hose-end sprinkler and the permanent
underground system. Even though a permanent sprinkler system can be more water efficient than
a hose-end sprinkler, both systems require little maintenance and apply large volumes of water
in a short time. The differences in these two sprinkler systems are in the cost, convenience and
efficiency. Permanent, sprinkler systems are much more expensive than hose-end sprinklers. Yet the
permanent system is much more convenient and can be much more efficient in applying water. In
Lawns
Most lawns receive twice as much water as they require for a healthy growth and appearance. The
key to watering lawns is to apply the water infrequently, yet thoroughly. This creates a deep, well
rooted lawn that efficiently uses water stored in the soil.
Trees and shrubs
All trees and shrubs need more frequent watering from planting time until becoming well rooted,
which may take two growing seasons. Once established, plants can then be weaned to tolerate
less frequent watering. Proper weaning develops deep roots and makes the plants more drought
enduring.
As with lawns, water established trees, shrubs and groundcovers infrequently, yet thoroughly.
In the absence of rain, most trees and shrubs benefit from a once-a-month thorough watering
during the growing season. Remember, normal lawn watering is not a substitute for thorough tree
and shrub watering.
The feeding root system of a tree or shrub is located within the top 30 cm of the soil and at the
‘dripline’ of the plant. The dripline is the area directly below the outermost reaches of the branches.
Apply water and fertilizer just inside and a little beyond the dripline, not at the trunk. Simply lay a
slowly running hose on the ground and move it around the dripline as each area becomes saturated
to a depth of 20 to 25 cm. For large trees, this watering technique may take several hours.
Eficient irrigation systems
The aim of any irrigation system is to give plants sufficient amount of water without wastage.
By zoning an irrigation system, grass areas can be watered separately and more frequently than
groundcovers, shrubs and trees. First, plants with similar water needs should be grouped. Water-
thrifty plants should be placed together and should be separated from grass and plants that depend
heavily on irrigation. The irrigation system should be designed after this. For example, properly
maintained sprinklers are effective for lawns while soaker hoses may be used to irrigate ground
covers. Irrigation schedule should not be rigid and should consider the rainfall pattern. Watering
should be done properly but not frequently. Rain sensors can be installed on automatic irrigation
system to prevent unnecessary watering when it rains.
Both sprinkler and drip irrigation can be incorporated to achieve water conservation in the
landscape.
There are two types of irrigation systems for use in landscapes—sprinkler irrigation and drip
irrigation. Within a water-efficient landscape, a combination of these two systems should be used
for watering lawns, trees, shrubs, groundcovers and flowers. Overall irrigation requirements will
vary according to plant species, soil type, rainfall, and temperature. Established, well adapted plants
require less frequent watering than newly planted trees and shrubs.
Sprinkler irrigation
Sprinkler irrigation is the most commonly used method of landscape watering. The two most
common types of sprinkler irrigation systems are the hose-end sprinkler and the permanent
underground system. Even though a permanent sprinkler system can be more water efficient than
a hose-end sprinkler, both systems require little maintenance and apply large volumes of water
in a short time. The differences in these two sprinkler systems are in the cost, convenience and
efficiency. Permanent, sprinkler systems are much more expensive than hose-end sprinklers. Yet the
permanent system is much more convenient and can be much more efficient in applying water. In
