After twenty years of landscaping on Fire Island off the south shore of Long Island, I made the move to another island, Manhattan, with some valuable knowledge and a lot to learn. On the positive side, I knew my customer base would be a similar affluent owner, with very high standards and expectations. I also knew the importance of planning and logistics from working in an isolated beach environment accessible only by ferry. These were valuable assets, as I had to quickly learn a whole new world of challenges on my new island. Traffic, elevator size, co-op boards, weight limitations, waterproof membranes, drip irrigation, fire codes, all became make or break issues to be successful in this new environment. I had my work cut out. Rooftop gardening, like seashore gardening, is a rewarding niche business. Even in a big city like New York, there are relatively few landscape companies that offer this service. This may be true in many cities across the country as most landscape firms originate outside the city environment and if successful they most likely will not have the need to develop the expertise necessary for this specialized market. These companies should think twice about the training their crew will need before attempting a rooftop installation.

There are good reasons to develop this expertise. Rooftop gardens sit upon the most valuable real estate in the country. Their ability to enhance the property and its values for relatively modest expenditures make them a popular amenity for developers and owners. Greenroofs popular for many years in Europe are just beginning to be introduced here with a potentially huge untapped commercial market. Budgets for all of these projects far exceed those for similar projects on the ground. There are good reasons for this as well.

The landscape team installed 76 lineal feet of mortared stone walls and 1,350 square feet of riverwashed stone for paths and patios.

The knowledge and skills needed for successful rooftop garden installations and maintenance are considerable. Safety must be given the highest priority due to the extreme consequences/ danger that any accident can have originating on a rooftop. Railing spacing or parapet heights must be strictly adhered to as well as fire codes, weight load limitations, and in multiple dwellings even handicap access issues may need to be addressed. Many projects will require consultation with a building or structural engineer to review live and dead load capacities, placement of planters and wind tolerance of any structures etc. Recently coop and condominium boards have begun to add extensive rules and regulations to their by laws for regulating terrace and rooftop gardens. It is not uncommon for a project to require several months just at the approval stage between engineers and Board meetings.

Located in Greenwich Village, the Weiss Studio project transformed an entire 4,092 square foot roof into an outdoor meditation garden.

Logistical issues are crucial to understand and plan for. In tall buildings, each and every item has to be transported through the building and its elevator(s). In lower buildings, hoists, cranes or boom trucks may be practical. Every aspect should be explored in the planning and estimating stage. Typical apartment building elevators have a hard time accommodating a sofa - try to get a 12-foot birch tree or even a 3-foot cube planter inside! Just about every surface that you traverse must be protected. Your crew may be very comfortable going across blacktop driveways and lawns but what about parquet floors and white carpet! Just one careless lean of a hand on a client's perfectly painted wall could ruin an otherwise great job. Everybody must be thoroughly instructed on safety issues. No tools or materials should ever be placed on the parapet ledges and anything that could be lifted by a sudden gust of wind must be weighted down at all times.

Another logistical factor to consider is the limitation you will face with respect to machinery you can use once in a building. It is highly unlikely you will be able to use a bobcat or a forklift. Just about everything is done with manpower and hand tools. Elevators rarely go up to the roof level. This means stairs must be used and size and weight must be carefully considered when lifting items up a flight of stairs. Every aspect of rooftop gardening is labor intensive. Add to that the delays of traffic, parking, waiting for elevators, restricted hours of operation and you quickly see how past estimating guides may need to be thrown out when you first start to estimate rooftop projects. Critical thinking to help develop this estimating and planning skill quickly is so important. When planning and preparing for a project it is essential that you realize that being a couple of bags of soil mix short, or needing an extra length of irrigation pipe or a spare chain saw blade can be a big problem in the middle of a city.

If you are going to be installing gardens on rooftops you must do your homework. Designers and even landscape architects are apt to make mistakes in this specialized field. You, as the landscape contractor, are expected to "know". You wouldn't plant a weeping willow next to a client's septic tank; its up to you to know not to exceed weight limitations or point loading restrictions. All roofs have waterproof membranes, which protect the structure from water damage. These membranes are installed by roofing companies and are typically warranted for a period of many years. You must take great care not to do anything which might void this warranty. Look for new products and materials that you can use in your work. In one project we had to devise a way to install a 4,000-plus square foot rooftop garden complete with stone walls, pond, stone patios and decking, and "float" it on the roof so as not to void the client's roof warranty. We created a whole new surface using 4-by-8-foot sheets of synthetic lumber sitting on protective dunnage "pedestals" and drainage system mats to accomplish this feat. Currently we are developing soil mixes using expanded slate and mineral components for their lightweight, drainage and water retention properties.

The installation of Tiffany's Garden included the transformation of a neglected rooftop space covering the top of the seventy-story high Trump Towers in the center of the Big Apple. The team created a playground, open lawn, herb and cutting garden, decorative vines and flower beds.

Microclimates on rooftops can play havoc with plant material. Rooftop conditions such as unobstructed sunlight, wind, lightweight soils and limited planter size coupled with the stress from reflected heat in the summer and rapid freezing in the winter means that some plants that do well in the ground below won't even survive in a rooftop planter. Irrigation and low voltage lighting systems are natural add-on services that are additional niche business. Irrigation usually takes the form of drip systems and they are critical to any rooftop garden. These gardens are often in the full sun and exposed to the drying effects of the wind as well. Add to that the limited capacity of the planter to hold water and it is easy for these gardens to require multiple daily waterings. These systems are the only way to go when you consider the pitfalls of relying on the client or his staff to do the watering. Systems should be designed to follow the local codes and because of the potential damage, a master valve should be installed limiting the danger of any one valve failing in the open position. Developing your company to service and maintain rooftop gardens is just as big of a challenge. As we all know maintenance is critical to keeping a garden looking good, yet the value placed upon it by many clients is often not so high. The effort, responsibility and risks are considerable. A maintenance route in the city traffic is unpredictable at best. Even when you get there access is not always assured, and you may not be able to stay a minute after 5 p.m. in coop buildings "to finish a job".

Town and Gardens, Ltd. has won 13 national awards for creating various urban gardens, including an upscale Manhattan residential rooftop application.

Did you remember to check all of the drains, irrigation, and everything else that would cause a problem or costly call back? If you can meet your client's expectations, however, you shouldn't have to worry about them shopping around for a cheaper service. In any case, this rarely happens in the urban setting where just finding a gardener is a feat. You will need to train your staff for their new environment and its challenges. Finding the best ways to carry things, cleanup, protect floors, etc. must be learnt. Your clients will also be looking to you to add seasonal plantings to their planters. Although they may be city dwellers, they are just as likely to be sophisticated gardeners with weekend homes, they are often aware of and looking for the more unusual "in plants".

The firm's president, Donald Sussman stands in front of the New York skyline, a site forever changed by the devastating terrorists attacks at the World Trade Center on September 11, 2001.

Maintenance takes on even greater significance when you consider the high cost of replacements. Replacing a dogwood that has grown for five years from 6-foot to over 10 is both labor and time consuming and probably not possible except with another 6-foot dogwood. All of the set up, protection, removal and carting make this one tree very expensive. This is another reason to build lasting and modular installations. Planters should be well constructed to both resist rotting and damage from freezing and to withstand the effects of being moved. This can happen at any time as maintenance on the building or roof may require everything be moved. Modular construction of all hardscapes, i.e. decks, planters, etc., will really pay off in the long run. Just wait until you get that call and your client expects you to be there the next day to make the garden disappear for however long the roof repair will take, then reappear like nothing has happened! I have made the transition and with great results. The projects that we are doing are extremely challenging and cutting edge. Our clients are continually impressed with the exciting new seasonal plantings and displays that we install for them. It's a big responsibility, but with a committed team such as I work with the "sky is the limit".