We are constantly approached on this subject. Frankly, it is almost always all talk, no action. However, recently there seems to have been a small break in any otherwise cloudy vista and highrise horticulture or ‘skyscaping’ is finding a growing number of enthusiasts. The mainstream media often uses the term ‘roof garden’ interchangeably for either just this or, more often, the ‘green roof’ planted for environmental reasons rather than occupant use. The two are not the same.
Check municipal bylaws and building codes
Condo owners usually do not own their balconies; check with management or condo board
If renting, read the lease – but the right to have plants on a balcony has been tested in court
Never, ever, place pots or other container on the balcony railing or ledge
Never, ever, suspend window box or other containers outside the balcony railing
Use lightweight planting mixes, not potting soil
Always use saucers under containers to avoid water draining down onto balconies below
Wind is the highrise and rooftop gardeners’ worse enemy; the higher up, the windier it will be
On rooftops, lattice in sturdy, securely fastened frames will soften the wind
Hanging baskets should be suspended from metal eyes, never hooks; even then may blow away
Heat from masonry and winds dry containers out fast, resulting in frequent watering requirements
Small waterfall and fountain pools dry out very fast; use ones containing several gallons
The sound of water falling masks city noises, relaxes but may send over-imbibing guests to the washroom
Water features and lights require power cords that pets may chew on
Pets may also chew on plants – make sure such are not poisonous to them
Concealed lighting is the most effective; lights should never shine into the eyes
Candles on balconies, like barbecues, are illegal in most municipalities
Using same style or appearance of containers throughout achieves most desirable effect
It is the plant, not the container that is the point of interest
Perennials, shrubs, evergreens and trees are a challenge even to experienced gardeners
Caution with vines; some such as Virginia creeper can damage masonry
Simplest, most effective are annuals and houseplants moved outside for the summer
On balconies choose plants suitable for the direction faced
Concentrate on achieving a lush foliage effect
Single colour flower plantings are striking against rich green backgrounds
Vegetables usually require at last a 10-inch diameter container
Some vegetables such as cucumbers, melons require insect pollination; bees rarely fly high
Many herbs will grow in 6-inch pots but probably will not survive the winter
All plants, but especially annuals, require liquid fertilizer every two to four weeks
Claims are made that pests don’t fly high; don’t believe it; keep insecticidal soap handy
Pigeons can be a major nuisance; netting is the only really effective answer
Squirrels can be a nuisance also; Canadian Living magazine warned of them on a 4th floor balcony
Like your ground level brethren, you will only succeed by experimenting, often over several seasons. But that, as with any gardening is half the fun. The other fun comes of being able to hold a garden party high in the sky. Never ever though stand back to admire your work.
Wes Porter is a horticultural consultant and writer based in Toronto. Wes has over 40 years of experience in both temperate and tropical horticulture from three continents.
