How green is your terrace?
The next time your friend boasts about her lush lawn, don’t turn green with envy—just invite her to your terrace garden. In cities where open spaces are a luxury, a lush green spread seems elusive. But nature lovers haven’t allowed urban concrete walls to stifle their desire to have a green patch of their own. They have found an answer, and solace, in terrace gardens.
If you, too, want your patch of freshness to stretch out on, soak in the sun and have your first cup of tea, here’s how you can create your terrace garden.
The first decision has to be about the size, and whether your terrace/balcony can take the extra weight. If you are building a house, then the terrace can be designed to take the load of the garden. In existing houses, however, one needs a minimum floor area of 10x5ft to build a terrace garden.
If one has a larger terrace, it’s better to seek professional opinion. “Usually, third and fourth floor terraces are not designed to take the load of the garden,” says Delhi-based architect Aniket Sharma. Gardens on higher floors are possible as long as these aren’t cantilevered balconies (where the beam is supported only on one end) and have enough space.
Where a garden can’t be created on a terrace, one can go in for an alternative—create a tiled surface, put potted plants on it and landscape it with pebbles, rocks and a small water pool. “Avoid a lawn and mud filling,” says Sharma.
To create a terrace garden, you need a minimum space of 150 sq. ft. A reasonable-sized lawn can be etched out in 400-500 sq. ft.
Also See The layers of a terrace garden (Reference Image Attached Below)
Before you start, make sure that the surface is waterproof. An effective drainage system is also necessary. Building a garden involves building one layer after another, each with its own purpose. Waterproof the surface using any water-resistant coating material, such as tapecrete. After applying the coat, lay the tiles. “Ordinary tiles can be used as they will be covered by earth,” says Sharma.
While laying the tiles, ensure that a slope is created for smooth drainage of water. The next step is to cover the tiles with riverside pebbles (Rs5 per kg) up to 2 inches in height.
Next, spread a woven roving sheet over the layer of pebbles. “This is a heavy coarse fabric that costs around Rs500 a metre for a 1.5m-wide roll and acts like a sieve, allowing water to percolate to the layers below,” says Sharma. Next comes a layer of soil about a foot thick. Mix bentonite powder with the soil to prevent the soil from coagulating when watered. “A bag of bentonite (which holds about 50kg of powder) should be mixed with 100 cu. ft of earth,” says Sharma (See “The Layers of a Terrace Garden”). The base for the garden is now ready.
What shows in a garden is the grass cover. Kanika Gupta, an architect with Design Consortium, a Delhi-based firm, suggests using carpet grass. “It costs Rs5 per sq. ft and is available in the form of square patches with 2-3 inches of earth,” she says. Once the grass has been laid, it takes about two weeks to set in. Within two weeks you can have a lawn ready.
The lawn should ideally be south- or west-facing so that it gets proper sunlight. However, if the garden isn’t going to receive much sunlight, go for the Nilgiri grass as it grows in shade. It costs around Rs20 per sq. ft. Selection1 is another variety of grass that grows well in most climates and gives a uniform look without scope for weeds.
Experts advise against Mexican or Japanese varieties. “Though thick, they are very sensitive and die easily when used, for example, while walking or when chairs are put on it for long,” says Gupta.
Apart from the grass, you can also put seasonal flowering plants or exotic shrubs. Choose plants that don’t have deep roots. Such plants can be placed in planters or big pots.
Cacti varieties do well on terraces as they are low on maintenance. Use bits of bamboo, a water body, and some artefacts to make the space more attractive. If you have less space, consider hanging baskets. A few bonsai plants can also be kept as they take less space and look good.
The garden can be used at night, too, with proper lighting. Use subdued lighting. “Make sure the fixtures are waterproof,” says Gupta.
The cost of the civil engineering work for preparing the surface is about Rs300 per sq. ft. One truckful of soil at about Rs1,000 is enough to cover a 350 sq. ft lawn. A tractor full of soil costs about Rs500 and is enough for 100 sq. ft space. Delhi-based Roshan Varma, 53, spent around Rs400 per sq. ft on his rooftop garden that is spread over 800 sq. ft.
You can engage an architect to create a terrace garden. The charges will vary. However, most architects do not take up terrace garden work unless it’s part of the complete house designing project. Alternatively, you can use the services of a landscape artist or hire a contractor.
You can employ a gardener for the upkeep. The best time to make a terrace garden is between April and May as grass grows best during the monsoon. Although a garden needs plenty of sunlight, you can build a pergola for shade and grow ivy or creepers. If you already have a shaded area, or an area which gets less sun, go for non-flowering plants. Also, bear in mind that the garden would require 30-40 litres of water a day.
The feel of damp grass under your feet is not easy to replace. A good enough reason to have some at home.