Rooftop Gardening in New York City
Explore the challenges and rewards of a rooftop garden
Amber Freda’s Top Three Design Tips:
- Invest in a drip irrigation system
“Watering by hand is not going to save you money. Containers dry out much quicker than most people anticipate. One client of mine installed $10,000 worth of plants and half of them died and were in need of replacement within a few months because she opted not to have a drip system installed.”
- Always think in terms of groupings
“Planters look best when grouped together, odd numbers are pleasing to the eye, try three or five.”
- Avoid the hodge-podge effect
“Pick two or three planter styles and two or three colors and repeat them throughout the space. Any more than this and you could end up with a rooftop garden that doesn’t look very organized.”
Every garden has its own set of unique challenges and blessings. This is especially true for those that garden on rooftops. Amber Freda, a New York City designer who has designed many rooftop gardens, likens gardening on a roof to gardening on a mountaintop. “The conditions are similar - you’re totally exposed to the elements and only certain types of plants do well,” she says. However, the same feeling you get when standing atop a mountain can also be experienced from a rooftop. For Freda, the view and experience far outweigh the trying conditions.
Freda thinks of rooftop garden design as a specialized field that is different from suburban landscape design. “In the city space is so valuable that having a rooftop garden is like having a second apartment, many of my clients double their living space,” she explains. Many similar challenges exist on rooftops as do at ground-level, but the solutions for these may be different. Wind, privacy and sun exposure are the main issues Freda faces when designing sky-high outdoor living spaces.
Tips for a windy rooftop:
- Select plants with small leaves, large leaves shred easily in the wind
- Use a heavy duty umbrella with a water filled base that won’t be blown off the side of the building
- Avoid lightweight furniture that may be blown around (plastic is not good for a roof garden)
If shade is sparse on a rooftop, there are a number of options for blocking the sun. Umbrellas work, as long as they are heavy enough to withstand wind. Another option is a retractable awning that can be stored when not in use so that it does not become tattered or faded. Finally, a custom pergola can be installed. “A rooftop pergola costs about $10,000 dollars, which can be cost prohibitive for some,” states Freda.
If privacy is a concern, Freda suggests a number of remedies. First, she says that planting a row of evergreens is a good option. Other privacy screening ideas include building a fence or installing a bamboo screen. For the most part, privacy can be achieved on a rooftop in the same manner that it can be achieved on the ground.
Tips for selecting plants for a rooftop:
- Evergreen conifers are a good choice because of their triangular, bottom heavy shape
- Multi-trunked trees, such as crape myrtles, fare better in the wind
- Flowering shrubs like azaleas and roses do well on rooftops
When it comes to selecting materials for a rooftop garden, you can achieve nearly any look. Freda has created rooftop gardens with themes ranging from traditional to Moroccan. For paving you can select from materials such as concrete pavers, stone or even composite decking. “Paving must be installed in a modular fashion atop a pedestal system that allows for proper drainage and regular access for maintenance,” notes Freda. Planters can either be purchased and transported to the rooftop or custom built. Freda especially like using fiberstone planters, which are a blend of fiberglass and stone. These planters are lightweight, but also develop a weathered patina over time just like stone.
- Pro Tip: Because New York City fire codes are so strict, I don’t specify grills or fire features for rooftop gardens. Clients typically pursue these elements on their own accord. However, we can install small electric fountains or even engineer a custom water feature for a rooftop.-- Amber Freda
One of the most challenging things about creating a rooftop garden is getting the construction supplies and materials up onto the roof. “Most buildings have an elevator which we can take loads up in, but some pre-war buildings do not and we have to use the stairs,” Freda says. Even in the case of having to use the stairs, Freda has never had a job that took more than a day to get the supplies in place on the roof. For special items, such as planters or furniture, sometimes she will use a courier service for delivery. If all else fails, a crane can be used to get the necessary items onto the roof. However, a crane costs about $25,000 for a day, while manpower costs around $1,000.
At the end of each day, no matter the challenges faced up on the rooftops of New York City, Amber Freda is still a strong believer in the benefits of rooftop gardens. “It’s like having your own oasis up in the sky with a magnificent view of the water or skyline,” she says.
New York, NY
Sarah Hutchinson, contributing writer for Landscaping Network