Try imagining a garden with large expanse of lawns, planted with wide variety of garden plants like palms, bamboos; flowering species such as roses, heliconias, dahlias; water lilies in a pool; orchids, and climbers hanging from tree branches, and forming arches over trellises.
One may have space, time, opportunity, and every other form of wherewithal for fulfilling such a dream garden, yet if water is a limiting factor, such dream will never come true.
In urban areas where water is scarce and bought at huge cost, nurturing such a garden is a dream only a few can accomplish.
Xeriscaping, where one can have a garden, but with limited use of water and minimal maintenance, can be the answer for such predicament.
Xeriscaping is a method of garden design that involves choosing of plants that can be maintained with little supplemental watering. With a little common sense and aesthetics, landscape can be organised in harmony with the site by using drought tolerant plant species and mulch material in a way to minimise the water use.
The concept of xeriscape may be applied to landscapes of any style.
How to design?
Water use in the garden can be minimised if a little care is observed during the planning phase.
The entire garden can be divided into zones with differential water requirements. The ‘oasis’ zone with relatively higher water use is usually earmarked in more visible places such as patios, entry areas, and beside the paths. Shaded areas alongside the walls are ideal for this zone as the water loss is less here.
The terrain shall be formed in such a way that the rain water from the rooftop or excess water in the garden will drain into this zone to cater to the needs of the plants. This zone requires more maintenance and is the garden’s most attractive area where flowering shrubs and colourful foliage plants are planted in groups.
Beyond the ‘oasis’ is a transition zone of moderate water use. This zone contains plants that require less frequent irrigation and usually less maintenance.
Further away shall be low-water-use zone, which requires no supplemental water or very infrequent irrigation during dry periods. This zone is generally positioned away from the access of visitors. The stress-tolerant plants are grown in this zone and also mulch is used to reduce the water use.
Mulch
Mulch is the cover material provided over the soil and around the plants to reduce evaporation, soil temperature and erosion. It also limits weed growth thereby reducing competition for water and nutrients.
Impermeable plastic mulch may be used in areas where the soil must be kept dry, for example, where the harvested water is being channelized from one area to another.
Permeable weed barriers, bark, gravel, wood waste or other porous mulches are better because they allow water and air to pass to plant roots. Organic mulches keep the soil moist and reflect less heat.
Using broken stones / pebbles arranged in decorative patterns is a good idea but they become very hot during summer and may limit growth of some plants.
Hence the plants which can tolerate high temperatures like cacti and succulent varieties should be chosen when such materials are used as mulch.
Irrigation
Irrigation is necessary in a xeric landscape, at least during the first few years while the plants get established, and during summer months thereon.
The irrigation system - whether automatic or manual - is an integral part of landscape planning. Irrigation channels for the all the three zones should be separate from each other, and managed independently with separate valves.
Efficiency of the irrigation system too plays a vital role in conserving water. Sprinklers are appropriate for lawn and ground covers, whereas drip irrigation is more appropriate for shrubs and trees.
Soil preparation
If soil testing is done prior to planting, it can help determine which plants are best adaptable to the site and which amendments are appropriate for improving soil for the selected plants.
Adding compost and small quantities of clay increases the water-holding capacity of the soil. Loosening the soil allows better infiltration of water and air and hence improves root development.
Plant selection
There are many attractive plants available for use in water-wise landscapes. Simply using certain cacti or a few hardy plant varieties may not be real xeriscaping. Beauty of any garden lies in diversity of leaf shades and flowering hues, and xeriscape is not an exception.
Most lawn grasses are on the list of thirsty plants, and should be avoided by selecting local grasses like dhoob or buffalo grass.
Maintenance
Maintaining the landscape in a right way cannot be forgotten, even in a xeriscape. Like any garden, xeriscape also requires operations like pruning, weeding and pest management, of course in a smaller scale.
Through xeriscaping the gardens can be kept healthier owing to lesser need of fertilizers and pesticides.
(The author is a forest officer and can be contacted at ‘nchandramohanreddy @gmail.com’)
