Xeriscape comes from greek work meaning 'dry,' so it does not mean plantings that require no water. It means designing and installing and maintaining a landscape that is adapted to dry conditions. Yet even in the desert it rains sometimes, so a xeriscape garden requires some water.
The Honolulu Board of Water Supply maintains a public garden in Halawa Valley (end of the road, Iwaena St.) that exhibits some of the plantings and techniques of xeriscape. BWS also has landscaped some of its urban pump station or other sites in a 'xeric' fashion. Examples would be the site on Kalanianaole Hwy. just West of Hawaii Kai, the pump station at Kapahulu Ave. near the Harding Ave. and freeway overpass intersection, and the stations on N. King St. and on Lunalilo Home Road.
Typical techniques include reducing the size of lawns to a bare minimum, use of rock or organic mulches, choice of drought hardy shrubs and small trees, and installation of drip systems for the shrubs and trees. The LEED (Leadership in Energy and Environmental Design) program now popular with architects (more than 300 in Honolulu participate in the LEED interest group) assigns enough points to the landscape that a building can actually get the basic level of LEED certification (40 points) if every landscape practice recommended were done!
Native plants are often used for their drought tolerant properties, though many exotics can perform the function as well. The Landscape Industry Council of Hawaii advocates that native plantings be used where possible, but does not oppose the use of well-selected and commonly planted exotics. Plants like sage ('Texas ranger'), prostrate cedars or carissa, zamia, crotons, ixoras, and many other common exotics can serve the purpose. With mulches and a drip system, once established, a xeriscape garden can use very little water indeed.
Lawns are generally very water thirsty. Certain lawn choices, though, for the limited areas where lawns are useful at a given site, will limit water use. The zoysia cultivars, especially, are drought tolerant, as is common bermuda. Cultural practices such as mowing higher in the summer, topdressing, aeration, and proper watering, can go a long way toward limiting the water use of a lawn. In practice, in reality, most lawns are really over watered. Lawns can do well on 2 to 3 waterings a week. Some sod farmers in wetter areas actually omit water altogether in the winter months, and they are selling prime looking product! An aerated lawn, in soil amended well with organic matter or kept topdressed with organic matter, will put any water applied to good use. And if that water is applied at night or before 7 or 8 in the morning, and sprinklers are not allowed to run beyond the ponding or run-off point, the maximum efficiency in watering can be obtained. A lawn will tell you by turning slighty grey in color, before wilting, that it needs water. By not scheduling watering until those slightly greying symptoms are incipient, keeping the lawn aerated and topdressed, and cutting properly, water use can be maximized, and a lawn can become 'unthirsty.' A healthy lawn can have roots going down 6" to 12" at least, and so can use reserves of moisture in the soil for longer periods between waterings.
Water conservation is everyone's obligation in an island society. Xeriscape gardening can go a long way toward conserving potable water. Use of effluent water (from septic systems, after primary treatment) has become standard in newer site utilities layouts, as in Kapolei on Oahu, and some developments in Kona. The most modern septic systems can deliver an output that would be generally safe to drink if the idea were not repugnant, and 'grey water,' or water used once in a kitchen sink or for a shower or bath, can also be routed to storage for landscape uses. Re-use of water is a xeriscape practice, too.
The Honolulu Board of Water Supply maintains a public garden in Halawa Valley (end of the road, Iwaena St.) that exhibits some of the plantings and techniques of xeriscape. BWS also has landscaped some of its urban pump station or other sites in a 'xeric' fashion. Examples would be the site on Kalanianaole Hwy. just West of Hawaii Kai, the pump station at Kapahulu Ave. near the Harding Ave. and freeway overpass intersection, and the stations on N. King St. and on Lunalilo Home Road.
Typical techniques include reducing the size of lawns to a bare minimum, use of rock or organic mulches, choice of drought hardy shrubs and small trees, and installation of drip systems for the shrubs and trees. The LEED (Leadership in Energy and Environmental Design) program now popular with architects (more than 300 in Honolulu participate in the LEED interest group) assigns enough points to the landscape that a building can actually get the basic level of LEED certification (40 points) if every landscape practice recommended were done!
Native plants are often used for their drought tolerant properties, though many exotics can perform the function as well. The Landscape Industry Council of Hawaii advocates that native plantings be used where possible, but does not oppose the use of well-selected and commonly planted exotics. Plants like sage ('Texas ranger'), prostrate cedars or carissa, zamia, crotons, ixoras, and many other common exotics can serve the purpose. With mulches and a drip system, once established, a xeriscape garden can use very little water indeed.
Lawns are generally very water thirsty. Certain lawn choices, though, for the limited areas where lawns are useful at a given site, will limit water use. The zoysia cultivars, especially, are drought tolerant, as is common bermuda. Cultural practices such as mowing higher in the summer, topdressing, aeration, and proper watering, can go a long way toward limiting the water use of a lawn. In practice, in reality, most lawns are really over watered. Lawns can do well on 2 to 3 waterings a week. Some sod farmers in wetter areas actually omit water altogether in the winter months, and they are selling prime looking product! An aerated lawn, in soil amended well with organic matter or kept topdressed with organic matter, will put any water applied to good use. And if that water is applied at night or before 7 or 8 in the morning, and sprinklers are not allowed to run beyond the ponding or run-off point, the maximum efficiency in watering can be obtained. A lawn will tell you by turning slighty grey in color, before wilting, that it needs water. By not scheduling watering until those slightly greying symptoms are incipient, keeping the lawn aerated and topdressed, and cutting properly, water use can be maximized, and a lawn can become 'unthirsty.' A healthy lawn can have roots going down 6" to 12" at least, and so can use reserves of moisture in the soil for longer periods between waterings.
Water conservation is everyone's obligation in an island society. Xeriscape gardening can go a long way toward conserving potable water. Use of effluent water (from septic systems, after primary treatment) has become standard in newer site utilities layouts, as in Kapolei on Oahu, and some developments in Kona. The most modern septic systems can deliver an output that would be generally safe to drink if the idea were not repugnant, and 'grey water,' or water used once in a kitchen sink or for a shower or bath, can also be routed to storage for landscape uses. Re-use of water is a xeriscape practice, too.
