In the heart of a city, it is challenging for gardeners to find a few inches of soil to call their own. An increasingly popular option – for both novice green thumbs and transplanted farmers – is to turn rooftops or balconies into a garden space.
Is a Rooftop Garden Right For You?
Rooftop gardens serve a variety of purposes. They can soften the edges of urban landscapes, expand living areas by making use of underused or wasted outdoor spaces, and provide fresh food, herbs, and flowers. In addition to being attractive, rooftop and balcony gardens are easy to care for, and require little maintenance once established. The only tending required is watering, harvesting, and the occasional weeding. You don’t need any experience to become an urban gardener, and it doesn’t matter how much space you have, or how much money. If you are willing to spend a few hours planning and planting, you can create a garden of some sort in your future.
There are a number of things to consider before you start planting your small urban garden:
Rules and Regulations
Before you haul bags of soil up to your apartment or condominium, it is important to review local zoning laws, building codes, rental property rules, or homeowner association regulations. The size and scale of the garden will determine how thorough this review is. Small container gardens are typically acceptable in most buildings, large rooftop gardens with small trees and shrubs will need more research.
Most flat-top buildings can accommodate a rooftop garden, but some older buildings may not have been designed to withstand any additional weight. If there is any question about the suitability of the roof or balcony it would be wise to contact an architect or contractor to determine whether the roof is designed to withstand additional weight, or how much weight the balcony can accommodate. Your specific situation will determine your design options and the materials you can use. If weight is an issue, you should avoid heavy pots and heavy garden soil in favor of light weight containers and potting soil mix. Styrofoam chips can be used for drainage instead of rocks or pieces of broken pottery. On the plus side, lightweight containers are also typically less expensive, offer greater design flexibility, and are easier to maintain than clay or ceramic pots. Plants in lightweight containers can also be easily rearranged and moved indoors in winter.
Another option for urban gardens is to use soil-less, or hydroponic, gardening, where plants are fed only by nutrients dissolved in water. These gardens are extremely efficient, and in areas where winter snows limit gardening to three seasons, the growing pots can be drained in late fall ahead of winter snowfall.
Food or Flowers?
The design of a rooftop garden ultimately depends on its purpose. There is a growing “local foods" movement in North America, and many people use container plantings to produce some or all of the fresh greens they eat, at least in the summer and fall. The Food and Agriculture Organization of the United Nations reports that 800 million people worldwide grow vegetables or fruits or even raise animals in cities, producing an astonishing 15 to 20 percent of the world’s food. While the vast majority of North American rooftop gardens are hobby gardens, many people are beginning to appreciate the freshness of their garden produce. They say it tastes better and is more nutritious than food that has travelled from half a continent away.
Although start-up and maintenance costs will vary depending on your enthusiasm and design, container gardening is typically the least expensive way to go. It is also worth considering the value of the harvest if you decide to grow vegetables; even a few hundred dollars’ worth of small fruits or vegetables can make a huge difference to a limited budget. For the cost of a packet of seeds, or a few small plants, urban gardeners can harvest fresh homegrown food that might not be available in inner city neighborhoods, or might be too expensive to purchase at a grocery store.
Design and Decor
Rooftop and balcony gardens can cover hundreds of square feet in metropolitan penthouses and urban farm roofs, or 10 square feet in an inner-city high rise. Regardless of space or budget your garden can meet your needs and reflect your personality and style. Containers and simple patio furniture are well-suited to smaller spaces. If space is really tight, you can take advantage of vertical space by growing things on trellises or installing a wall fountain, and by hanging plants, wind chimes or bird feeders from eaves or overhangs. A variety of heights, textures, and forms will also create visual interest. If the goal is to create a private green escape, vertical features also help create an atmosphere of privacy. In any garden, it is important to avoid a cluttered effect. Resist the urge to incorporate too many plants or furnishings, and try to balance empty spaces with plantings, so there is enough room to get around comfortably. If you plan to use the garden year-round, containers can be replanted or moved with the seasons.
Many, if not most, herbs, vegetables, and flowers will do well in rooftop or balcony gardens if basic light and water conditions are met. Depending on the available space, and whether containers are used or small raised beds, options include tomatoes, radishes, onions, peppers, and leafy greens such as spinach, lettuce or Swiss chard. Carrots, potatoes, strawberries, beets, cabbage, broccoli, cauliflower and beans are also options if space is available. Herbs lend themselves quite well to small pots, and can easily be moved indoors to supply fresh herbs all winter.
Rooftop and balcony gardens can be windier than ground level gardens, so it is important to consider the need for windbreaks in the garden design. Trellises can serve a dual purpose of supporting vines and tall plants while breaking up the flow of the wind through the garden. Lattice and trellises are often a better choice than solid windbreaks that might topple in high winds.
Regardless of the type of garden you plant, you will need to have a convenient source of water nearby. For a small balcony container garden, watering cans will be sufficient. Like outdoor flower pots in gardens everywhere, whether ground or roof, hot weather will mean containers need to be watered daily. If your rooftop garden is more elaborate or covers a larger area, consider installing a water storage system of some type, or hooking up an automatic watering system.
Whether you want to harvest fresh greens for a salad, enjoy small pots of flowers, or just spend time relaxing in an outdoor space, a rooftop or balcony garden will become a much-valued addition to your urban home.