Tomatoes and carrots can thrive on your rooftop

Tomatoes and carrots can thrive on a rooftop or fire escape just as well as they would in a backyard. And in addition to the benefits of being aesthetically pleasing and offering easy pickings for a fresh salad, a green roof will act as insulation to keep a home warmer in the winter, and absorb sunlight to keep it cooler in the summer.

If you've never been much of a gardener before, fear not, says Justin Hancock, senior garden editor at Better Homes and Gardens magazine. You'll be surprised how simple it is to sprout corn or cabbage.

"Gardening has gotten a bum rap, mostly because people make it seem harder than they need to," Hancock said. "Either that or people think about having to help their grandparents weed the garden and deal with the bugs, the heat and the dirt. But if you're doing this on a rooftop or a balcony, it's not hard at all."

An urban garden can be as sophisticated as a botanical oasis or as simple as a large planter box with a few favorite herbs.

"I would say most vegetables can be grown with general ease," Hancock added. "As long as they get the amount of moisture and light that they need, most will do pretty well for you."

What you'll need

• The bigger the container, the better. Wide-rimmed plastic or terra cotta pots with drainage holes are great if you have limited space, but raised beds and large planter boxes are best. They can be watered less frequently, are less awkward to move around and won't be pushed over by strong winds.

Your plant bed should be at least 8 inches deep and no wider than 5 feet, so that you can tend your garden without having to step into the soil. Building your own is relatively easy using pressure-treated lumber boards that are 6 inches wide and 2 inches thick, stacked one on top of the other. Attach the boards to corner posts using galvanized deck screws.

Dry-stacked field stones are also a good option for a retaining wall.