Before designing and planting a balcony or roof-top garden, think carefully about the style you’d prefer, how often you’ll entertain there, and whether you may want to grow some vegetables or herbs. But, most importantly, consider how much time you will be able to give in order to maintain your new urban oasis.

Essentials before you begin

One of the first things I say to people considering a balcony or roof garden is that it’s essential to check with a qualified architect or structural engineer first to find out how much weight your roof can take and whether planning permission is needed. You’ll also have to ascertain whether your balcony or roof garden is waterproof. This may sound strict, but it’s worth following the correct regulations initially to avoid paying for the damage if, for example, you flood your home or make the roof or balcony collapse under the weight of heavy containers. Ideally, position containers on the perimeter of a balcony or roof garden near load-bearing walls or over a load-bearing beam or joist.

Dreams and possibilities

You will then need to give some thought to the plants that will actually thrive there, as well as how you want to use your new outdoor space. The points I’ve outlined here are not intended to be rules because there are always exceptions (and I don’t think that being too stringent makes for much gardening enjoyment). However, plants are living things and following these guidelines will help your garden flourish:

Be selective Choose containers that create focal points and spend money on a couple of larger containers rather than on lots of smaller ones. Too many plants or ornaments can make a small space look overcrowded.

Think about light When container gardening, tailor your planting to the available light. If you have low levels of sunlight, use shade-tolerant plants with lush foliage such as hostas, heucheras, ivy, and grasses.

Create a backdrop Start with evergreen plants such as box and sweet bay. Lavender also provides a year-round green base, but it won’t flower all the time. Then, add your favorite colors with flowering perennials such as Agapanthus, bleeding heart, campanula,and clematis that have a long blooming period and will come back next year.

Use odd numbers Planting in odd numbers gives the most aesthetically pleasing results, so plant one, three, or five plants in a container.

Restrict the color palette Don’t overdo the number of colors in a planting scheme; it will look too busy and make your garden look smaller.

Start with herbs It may not be possible to grow an entire vegetable patch, but start with a small container or window box packed with your favorite herbs or salads. Not only do you get the satisfaction of growing your own produce but these crops can also be used in cooking. Mint, chives, rosemary, parsley, and a salad mix are good varieties to start with.

Grow vegetables Once you’ve mastered herbs, move on to other crops. Vegetables such as tomatoes, salad onions, carrots, eggplants (aubergines), beans, cabbages, potatoes, and radishes, as well as fruits like strawberries, will all thrive. Remember that the amount of sunlight will influence what you can grow.

Care and maintenance Whether you are growing ornamental or edible plants (or both), follow regular watering and feeding routines to get the best results.