A roof garden can be an option for people who have limited yard space or for anyone with a flat roof who wants to garden up in the sky instead of on the ground. Think of a roof garden as a container garden. Before you start gathering materials, however, do some thorough investigation and planning.
- You will need to ensure that the roof is strong enough to support the size garden you imagine. Soil is heavy and mature plants laden with fruit and vegetables are heavy. Generally, around the sides is the best spot to put your garden plants because it has stronger support. Consider how you will get water to your plants.
- Some type of rainwater recycling system is the best idea for a roof garden. This can be as simple as barrels that collect rainwater. You may choose to have raised garden beds or containers. You don’t have to put the raised beds on the floor – they can be elevated on tables or benches, allowing easy watering. A square foot garden is perfect for the roof garden.
- The square foot garden grows more vegetables per square foot, requires less water, takes up less space, requires less maintenance and less soil than a regular garden.
- Other considerations are exposure of plants to increased wind, elements and more extreme heat. The roof garden will radiate heat from the roof, plus the temperature is around 5C higher than temperatures at ground level. So you may need to install wind shields and overhead cover for shade, and you will need to choose plants that can tolerate the extra heat. Mediterranean plants are ideal.
- Trellises and other vertical gardening supports are a great idea for the roof garden – providing growing space upward and adding interest, drama, and even shade.
- Additionally, you will need to check with your local government to ensure that you are within zoning restrictions to have your roof garden.
- Your raised garden beds and plant containers should be lined and given adequate base drainage before you fill them with a lightweight planting medium.
Easy to Grow Staples of the Container Garden
Heat tolerant, tomatoes grow great in containers, making them an excellent choice for your roof garden. They’re also the world’s favorite vegetable (actually it’s a fruit). Remember they will need support such as a cage or stake, unless you choose dwarf varieties.
Peppers tolerate heat well and grow excellently in containers. Grow all kinds of peppers.
Grow them in a container and provide a trellis support for the vines to climb vertically.
Herb Gardening in the Roof Garden
Herb gardening can be accomplished in the roof garden as easily as vegetable gardening or flower gardening. Simply choose herbs that can be grown in containers or in a square foot garden bed/box. Some herbs can grow quite tall – consider their mature size when you plant them. Although a wonderful thing about a container garden or a small raised garden bed is that your gardens are movable.
Inspiring Roof Gardens
For inspiration, read about The Hanging Gardens of Babylon (an ancient wonder of the world) or visit the Derry and Toms Garden in London, one of the world’s most famous roof gardens of modern times.