Although balconies are common features in many Housing Board flats and condominium apartments, their design possibilities are often overlooked.

Many people use the extra space for practical reasons, such as for hanging laundry or as storage. But balconies - which are precious nooks to enjoy fresh air and sunshine without leaving the home - have the potential to be so much more.

You can get some ideas on how to turn your balcony into a beautiful retreat at the Singapore Garden Festival when it starts on July 23.

For the Balcony Gardens competition, five designers will create beautiful mock-ups of balcony concepts featuring plants, water features and furniture in a 3m-by-3m space.

The five designs will be judged by a three-member panel that includes Mr Bob Sweet, who was the Royal Horticultural Society's head of judging.

Gardens are awarded either a bronze, silver or gold medal - more than one garden can win in each category - and judges will be looking at the overall theme, styling, how the garden was constructed and how plants were used.

There will be only one Best of Show medal, given to a gold-medal balcony garden that has the highest overall score.

Held at Gardens by the Bay, the sixth edition of the Singapore Garden Festival will run from July 23 to 31. Organised by the National Parks Board (NParks) and Gardens by the Bay, the biennial event is bigger than before, spanning 9.7ha at the Marina Bay attraction. The Straits Times is the official media partner.

Other highlights include show gardens, an orchid extravaganza at the Flower Dome and a marketplace where gardening and landscape products will be sold.

New events include a terrarium exhibition and a Landscape Design Challenge, where teams of students will be tasked to transform a 9 sq m space into a garden in five hours.

Tickets are on sale at various locations. Head to visitor service counters at the Singapore Botanic Gardens and ticketing counters at Gardens by the Bay or go to www.singaporegardenfestival.com and www.gardensbythebay.com.

Subscribers to The Straits Times get an exclusive treat. In partnership with NParks, 50 subscribers of the newspaper will each win a pair of tickets to the festival's gala opening night on July 22.

Direct subscribers can log on to the SPH Rewards Portal (www.sphrewards.com.sg) till Friday and download a voucher to take part in the lucky draw.

Meanwhile, if you are just looking to get started on redecorating your balcony, balcony garden designers and edible garden experts share their tips on making every square foot count.

Spicing up her balcony

Like many home owners who are growing edibles for the first time, housewife Samantha Ching-Uy was nervous about how to keep them alive.

The 39-year-old says: "I've always wanted to have an edible garden, but when I go to plant nurseries to have a look, I'm overwhelmed. There are many seeds to choose from, but there isn't much detailed information on how to care for them."

But because she wanted her own supply of naturally grown herbs, she engaged Ms Cynthea Lam of Super Farmers, an urban-gardening company, to help her start a herb garden in the balcony of her four-bedroom condominium in Thomson Lane.

In the small balcony measuring 1.3m by 2.8m, they placed a three-step wooden shelf. Nine pots filled with aloe vera, spring onion, basil and rosemary went onto it.

Ms Lam will teach Mrs Ching-Uy to look after the plants, such as when to fertilise and water them, how to spot and deal with pest infestations and what to do when the weather changes. She also provided a starter kit that includes a gardening tool set, organic fertilisers and naturally derived pesticides.

Tending to the garden is a way for Mrs Ching-Uy to bond with her older daughter Alessa, aged seven. Her husband works in a bank and the couple also have a 23-month- old daughter, Adriana.

She has big plans for her garden, hoping to have more plants and to put them in planter boxes.

Alessa also wants to try growing strawberries in Singapore.

Mrs Ching-Uy says: "I want it to look like a garden instead of having just stands.

"I want to see more soil and eventually get it to look like a veggie patch."

Wilderness at home

This tiny balcony in a Kembangan condominium is a small but concentrated patch of wilderness.

In that 2.5m by 0.6m space, there are about 200 plants growing from pots, with some hung overhead, and creepers such as Piper ornatum climbing the walls.

Forget about seeing the balcony floor - it is crammed with potted plants. Peer between the leaves and you will see a 1m-long fish pond.

The green-fingered owner, Mr James Ip, is an IT consultant in his late 40s. His friends call him "plant- crazy James" and the bachelor has loved plants since he was a child.

The work on his balcony started 10 years ago with the pond, which was flanked by a Dracaena marginata (commonly known as the dragon tree) and papyrus reeds.

Over the years, he added more plants to this simple arrangement, paying attention to "silhouettes, patterns and textures". Just two years ago, he started hanging plants overhead to create a more visually interesting garden.

His favourite is the fern. He has maidenhair fern, which has soft, lacy leaves; staghorn fern, so-named because its leaves resemble antlers; and long, hanging tassel fern, among others.

The garden spills over a little into the living room - his way of bringing the outdoors inside - and he has a small collection of succulents in his yard, next to the kitchen.

Mr Ip is an attentive and meticulous gardener. As the balcony is west-facing, it gets the brunt of the afternoon sun. So he places plants with larger leaves in front to shield those that are more sensitive to the sun.

He says he has grown realistic about what can survive on his balcony. Once, he tried to grow Medinilla magnifica, native to the Philippines, which, in full bloom, is supposed to have drooping clusters of flowers. However, no flowers appeared as the balcony was too warm.

Gardening, he says, is important for his sanity. "Working on my plants is relaxing and helps me to unwind after the daily grind."

Getting started

If you want some greenery in your high-rise, balconies are a good spot to bring the outdoors inside.

Here is a guide on what to consider before you get started.

AESTHETIC BALCONY GARDEN

Size matters

The rule is: the bigger your balcony, the bigger the plants it can take.

Mr Lee Meng Kwan, 50, of Hua Hng Trading, a wholesaler of plants and landscaping materials, which also designs balcony gardens, says bigger balconies look better with bigger, leafier plants, such as bird's-nest ferns.

For a touch of colour, you could plant bougainvillea or, if you want something sturdier, a frangipani tree, which has lovely white flowers.

For smaller balconies, he recommends using shallow and wide pots as they can hold more plants and are easily moved around for different configurations.

One suggestion is to create a succulent garden with cactus and agaves. Another popular choice is the Sansevieria trifasciata, or mother-in-law's tongue, which grows upright and saves space.

As for fixtures and furniture, there is more room to play with in larger balconies.

Ms Joyce Tan, a marketing manager at outdoor living specialist company Absolut Outdoors, advises home owners to think about what they want to use the balcony for.

She says: "Is it for enjoying the view or letting your children play hopscotch? Do you want a sandbox for the children to have a sensory experience or, if you have pets, do you want to let your cats and dogs have exclusive use of the balcony?"

After that, you can decorate accordingly, whether it is to, say, create a children's play zone with a swing and sandbox or a lush retreat with faux green walls and a water fountain.

Some people even put dining sets in bigger balconies, says a spokesman for Qanvast, an app for interior design ideas in Singapore. He adds: "Balconies are typically used as a lounge space in smaller homes."

Get your light and wind speed right

Find out how much sunlight and wind your balcony gets throughout the day and put in appropriate plants.

Mr Gary Nai, 54, managing director for Greencrafts & Design, a landscape design company, says higher floors tend to have "harsh settings", being hot, dry or windy.

"This is different from being on the ground, where there is moisture and more shade."

Mr Andy Eng, 39, project director at Nyee Phoe Flower Garden, says: "For floors which have strong winds, home owners should avoid plants with brittle leaves as they will break off easily."

When in doubt, ask the plant nursery staff for advice, Hua Hng Trading's Mr Lee says.

Plan a realistic budget

If you are on a budget, a few potted plants from a nursery could cost about $50, depending on size or plant variety.

If you want a full garden with infrastructure such as decking, planter boxes, a vertical garden system, illumination, an automated watering system and a water feature, be prepared to spend a five-figure sum, says Mr Josh Theoh, 35, lead landscape architect and founder of design and consultancy firm Passionscape.

Plan for proper maintenance

A popular request home owners have for balcony garden designers is to craft a low-maintenance garden.

Nyee Phoe Flower Garden's Mr Eng says that while his clients want a garden, they travel often and worry about plants dying.

"Sometimes, they want plants which need no maintenance, which is impossible," he says.

His solution is to install an autoirrigation system or choose foliage plants instead of flowering ones, which are the most difficult to maintain because they need to be trimmed.

Absolut Outdoors' Ms Tan adds that the market has a good range of artificial products to complement a balcony garden. For example, the company installs artificial vertical gardens for owners who have trouble keeping a live vertical garden.

She adds: "Other than wooden decking, home owners also like to use artificial grass as their outdoor flooring. The green helps to set the outdoor mood and it requires virtually no maintenance. It's easy to vacuum and wash."

EDIBLE GARDEN

Start with the right crops

A hot garden trend at the moment is to grow your own food. You can turn your balcony into a vegetable and herb patch and get fresh edibles straight off the plants.

Mr Benjamin Ang, 27, a manager at the Horticulture and Community Gardening Division at HortPark, advises new urban farmers to assess the sunlight conditions of their balcony first.

His balcony does not get much sun, so he grows herbs and vegetables that thrive in partial shade, such as rosemary, lavender and chillies. Some other easy edibles to start with include basil and mint.

Understand your plants

Find out what your edibles need to grow better, says Ms Cynthea Lam, 39, founder of Super Farmers, an urban-gardening company.

In general, when it comes to watering, she suggests using your fingers to check if the soil is still moist from the last time it was watered. Occasionally, turn the leaves over to see if the plant has been attacked by pests or eaten by caterpillars.

Mr Ang says a common misconception among urban farmers is that fertilisers are harmful for the plant when they are necessary as they contain elements such as nitrogen and potassium, which are required for plant growth. He says: "Read up rather than follow hearsay or what you think is right. There's a wealth of resources online."

Ms Lam says new gardeners should not throw in the towel when their plants die. "It is a mindset. Some people have no interest in gardening and give up so quickly. Keep growing and don't give up. Maintaining a herb garden is no different from having a pet which needs to be fed, walked and entertained."