Roof Gardens

No matter where they are, roof top gardeners are a breed apart. I have seen meadows growing in eaves and roses trailing into the sky when space is at a premium. In sheltered city gardens, I have seen mature trees thriving and spotted allotments and orchards.

There is no easy way to grow up in the sky, but with a little planning and an understanding of what you have to deal with, you can achieve a lot. The challenge is greater than gardening on the ground, but it’s so inspiring!

There are more than half of all new homes being built today that are apartments, so rooftop gardens and terraces are becoming increasingly popular and vital to maintaining a green environment. If you need a financial incentive and think it’s too much work, then research has shown that even the tiniest balcony or terrace can add 8% to a house’s value and 25% to a restaurant’s revenue!

Roof gardens are often seen as a modern phenomenon, so I’d like to show you where we first created them.

Babylon’s hanging gardens are probably the most famous roof gardens in history. This was probably built by Nebuchadrezzar II for his wife Amytis, who missed the greenery of her homeland, Media, during the rebuilding of Babylon. We only know about the gardens from writings made 200 years after their destruction by Xerxes I around 482BC. According to its description, it has lofty stone terraces, closely reproduced mountain scenery with plants that mimic the mountains of Media. Siculus (a Greek historian from the 1st century AD) describes them as being 100 feet long by 100 feet wide and built in tiers like a theatre. Plants were carried in vaults, with the highest reaching 70 feet. Gardening on a grand scale while respecting weight limits!

Pompeian roof gardens

Pompeian roof gardens were the next significant example of roof gardens. In 79 AD, Mount Versuvius erupted, preserving almost perfectly what we would define as a roof garden terrace. A U-shaped terrace runs along the northern, western, and southern boundaries of Pompei’s Villa of the Mysteries, where plants are planted directly in the soil. A colonnade supports the terrace on all three sides. This served as a tomb for those escaping the falling ash. By carefully excavating and pouring plaster into the root spaces, we have identified the plants that were used.

Some of the other middle-ages gardens include those at Mont-Saint-Michel in France, the Medeci garden at Careggi in Italy, and the Aztec City of Tenochtitlan razed by Cortes in 1521. In the 17th and 18th centuries, the Kremlin Place in Moscow was notable for its roof gardens. It was destroyed in 1773 for the current Kremlin to be built. In the 17th century, the Russian nobility had extensive gardens and installed a two level hanging garden on the upper level with two terraces descending almost to the edge of the Moscow River. Built on vaults, surrounded by stone walls, and with a 90 square metre pond filled with river water. Built in 1681, the lower garden also has a pond. Plants were in boxes, with an emphasis on trees, shrubs, and vines. Paintings gave the illusion that the space was larger.

A popular movement in the early 20th century was the theatre roof gardens in the US, such as the American Theatre in New York City, where the term “roof garden” was coined.

Garden theatres

The first was built by Rudolph Aronson, who was inspired by the Parisian theatres and the high cost of land! He built the first theatre in the world with a stage specifically for summer performances on the roof. Oscar Hammerstein’s Olympia Music Hall was one of the most imaginative garden theatres, built in 1895 entirely enclosed in glass with a constant stream of water pumped to the outside edge of the roof to cool visitors and mask the sound of street traffic. There were still simulated lakes with live swans gliding across their surface, and they still used the rocky mountainside look. In the 1920s, air conditioning and changing tastes led to these theatres closing down and being demolished one by one.

Over the years, two gardens built before World War II have inspired roof garden designers. There is the Derry & Toms Garden in Kensington and the Rockefeller Garden in New York. Also influential is the Union Square garden in San Francisco, which has recently been redesigned with a lot of praise.

As part of the famous department store, Derry & Toms opened a roof garden in 1938. Until 1978, it hosted events with nobility and royalty. It has been restored and given a new lease of life by the House of Fraser group. There were more than 500 trees and shrubs in the original garden. In recent years, poor maintenance, aging, and drought have taken their toll, but it remains a great example of what you can grow. The Spanish gardens, Tudor gardens, and English woodland are the main features. For modern requirements, such as elevators and lawns, the garden has been greatly altered.

One of the Rockefeller Center buildings was designed by the same architect as Derry & Toms, Ralph Hancock. He was also a fellow of the Royal Horticultural Society. However, the gardens are much simpler, with central parterres of lawn, trimmed hedges of privet, and tiny fountains and ponds about 2 inches deep. Derry & Toms gardens were completed shortly before these. The chief horticulturist for the site designed more elaborate Mediterranean gardens. The elevators hauled 3000 tons of topsoil!

As gardens were once designed for individuals and public areas, now roof gardens are sprouting everywhere and apartments without outdoor spaces are rare. But we owe our smart London roof gardens to a long history of innovators leading the way to greening our cities.