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Combining Urban Rooftop Farming with Public Transportation

Green Team at Green Roof Technology, - Saturday, June 22, 2013

By: Jörg Breuning

Photo: Bauder, SSB Stuttgart Germany

Germany is the country of inventors, poets and thinkers. According to historical research, rooftop farming has been a long tradition since the mid-evil times in the dense cities of Europe. The lack of open space inside city walls brought people up to their roofs. Because there was also no efficient sewer systems, it was easy to utilize the organic remains to fertilize and grow plants. Throughout the centuries, survival proved to be a tough journey, mainly caused by overpopulation. When it became too dangerous to venture from your house, people discovered their roofs as additional space for growing their own food in order to overcome these rough years. Currently we are witnessing this growing trend once again in many metropolis areas in North America. The motivation is still the same, jobs can be hard to find, it's difficult to stand out when everyone is competing for essentially the same things.

Luckily our sewer systems are more advanced today, synthetic fertilizers are cheap and these farms do not depend on organic remains anymore. The quality of food should be acceptable in this respect - disregarding the extreme rates of pollution within cities.

However, let us backtrack to the topic of inventions.

Growing food on rooftops of the public transportation system (buses and trains) can help to combine two major needs of urban citizens. The added value is that your transportation systems are now also farmer's markets and while riding the bus home from your cubical, you can manage all your food shopping in one step including fresh produce grown directly above - on the roof! If the roof of the transportation vehicle is a semi permeable membrane, the carrots actually can be harvested from the inside. How convenient would this be? Depending on the crop, the sunny routes have more sun loving veggies and the transportation system manages regular crop changes from a more balanced and diverse food supply. Think about all the new jobs being created!

Sure, this technology is just in the beginning stages, but with the current hype for locally grown and diverse environmental approaches, it is just a matter of time until people will also jump on the bandwagon (or bus). It is just as ideal to look for some free advertising space in the press.

So, see you on the Lemon Line or drop me a line from the carrot bus (they should probably invest in free WiFi too).


Jörg Breuning welcomes people who want to learn from decades
of green roof experience -

The Time is Right for a Natural Swimming Pool

Green Team at Green Roof Technology, - Tuesday, May 21, 2013

by Andrew Yanders

Another beautiful weekend has passed us by.  The sun was shining high in the sky and it was very warm, bordering on hot.  Thankfully Memorial Day is just around the corner and pools all across the country will be opening.  Cooling off will simply be a dip away.

Like many of my friends, traditional chlorine pools no longer interest me in the least.  They are actually a thing to be avoided.  I am lucky to be from central Pennsylvania where fresh mountain-fed streams and lakes are abundant.  Whenever I’m home in the summer, my first thought it to go to the mountains and find an ice cold stream or ‘dam’ to swim and relax in.  The water is refreshing and the complete immersion into nature is just what the soul requires. 

Unfortunately, this level of natural luxury isn’t available to all, whether due to geography or downstream pollution.  For those who do not have easy access to streams and lakes, a natural swimming pool is the next best thing.  Natural swimming pools can be designed for sizes ranging from single-family backyards to public town pools. 

Natural swimming pools are a careful orchestration of various plant types that work together to filter the water to pristine levels.  This system is cared for much like a water garden and is great for those with sensitivity to chlorine.  Natural swimming pools are naturally filtered and cleaned, providing an unparalleled swimming experience in the comfort of your own garden

These fantastic pools are stunning all year round, during the winter they can freeze without a problem and during the spring and summer the plants put on a glorious display of blooms.

Green Roofs and Stormwater Fee

Green Team at Green Roof Technology, - Friday, May 17, 2013

Green Roofs Can Reduce Stormwater Runoff, Reduce Stormwater Fees!

By: Rebecca Gullott

Not many Marylanders are happy about paying the new stormwater fee or “rain tax” as it has come to be known. The county imposed fee is based on the amount of impervious surface such as rooftops and driveways on each property (cost-by-cause principle). In Howard County alone there are over 19,000 acres of impervious surfaces that contribute to pollution of local streams and the Chesapeake Bay. 19,000 acres are almost 30 sq miles or 11% of the counties size- more than double the size of all water ways in the county! No wonder that Stormwater runoff is responsible for over 20% of pollution into the bay.

Those wishing to lessen their stormwater fee can reduce the impervious surface area on their property through smart design and management practices. Howard County is providing instruction and incentives for citizens to do just that. Howard County Stormwater Management Division has partnered with several organizations including the University of Maryland Extension to help citizens take control of their environmental impact. Rainscaping workshops will be offered this summer to show residents how to plant and maintain rain gardens and native species; as well as compost waste and use rain barrels to collect roof runoff for use in lawn and garden irrigation or car washing. Howard County is offering free rain barrels at the Alpha Ridge Landfill select Saturdays April through September. Other Maryland Counties have similar programs so check your county’s website to see what offerings are available.

Property owners can receive credits for on-site improvements that reduce impervious surfaces. Whether it’s establishing a rain garden in the yard or incorporating planted areas or green roofs into the company’s parking lot, these incentives may encourage citizens to take control of their environmental impacts. These changes may help to reduce the need for future stormwater fee increases and promote a healthier Chesapeake for years to come.

The possitive impact for the environment by implementing cost-by-cause fess is very effective in many other counties and States in the US and over decades in Europe.

Europe has Banned Potent Pesticides

Green Team at Green Roof Technology, - Wednesday, May 01, 2013

By: Samantha Yurek

Honey bees are the most significant pollinators on earth. They are responsible for pollinating approximately 80% of our flowering crops.  "If the bee disappeared off the surface of the globe, then man would only have four years of life left."  It may be questionable to whether this quote came directly from Albert Einstein himself, but it is indisputable that the honeybee population is essential for maintaining the quality of life we enjoy so much.

Yesterday, the European Union stood up for the honeybees and banned a group of potent pesticides classified as neonicotinoids. Neonicotinoids are commonly used to prevent pests on plants such as soy, corn, canola, sugar and wheat. Evidence has surfaced that these pesticides are responsible for the honeybee decline or Colony Collapse Disorder, a phenomenon that appeared in 2006. Neonicotinoids are known to agitate the honeybee's reproduction processes, communication and navigation skills, along with weakening their immune systems. 


We take pride in avoiding herbicides and pesticides at Green Roof Technology. A green roof is an excellent habitat for all pollinators, especially honeybees. Watch a video about beehives on rooftops in Baltimore or learn about the plants you may choose specifically to lure these fuzzy creatures to your green roof!

Photo Credit: Green Roof Technology

Extensive verses Intensive - Which Would You Choose?

Green Team at Green Roof Technology, - Tuesday, April 16, 2013

By: Samantha Yurek 

A lot of thought goes into the design process when starting a green roof project. One of the biggest questions involves the type of green roof you want; extensive or intensive? This decision will dictate everything that will need to happen for your green roof to become a success. Let us take a quick look at the differences between intensive and extensive green roofs.

Extensive Green Roof: Swarthmore College of PA, Photo Credit: Green Roof Technology

Extensive green roofs are considered the simpler version because the roof structure is usually equipped to withstand the little bit of extra weight. With only a maximum of 6" of growing media and mostly ground cover covering plants, and extensive roof is certainly of a lower profile. The plants consist mainly of sedums and other succulents, herbs, grasses, mosses and low-growing perennials. An extensive roof is mainly for environmental benefits and and occasionally accessible to the public. Extensive green roofs can be excellent combined with Solar panels what increases the environmental benefits and increases return of investment substantially.

Intensive Green Roof: The Ledge Restaurant in Boston, Photo Credit: High View Creations

Intensive green roofs on the other hand can become quite extravagant. The roof must be very sturdy in order to hold foot traffic, deeper growing media and larger plants. The plants found on an intensive green roof range from shrubs and perennials to larger trees. Accents such as ponds and recreational spaces are a possibility. An intensive green roof is a busy and more expensive system with more potential for greater designs and biodiversity.

First International Bird Airport on Intensive Green Roof

Green Team at Green Roof Technology, - Monday, February 18, 2013

 Ornithoport in Bonn

Picture: Bundeskunsthalle

Airports are plentiful in our world, but a unique concept involves creating airports specifically for birds.  An exhibition on the roof of the Art and Exhibition Hall over the summer of 2012, highlights this common area as a destination point for birds.  To aid this bird airport (ornithoport), nesting boxes and feeders were installed, as well as approach and departure structures, complete with flashing airport signals and safety announcements.  All together this presentation is not only an awesome art piece, but probably the best landing facility for birds from all around the world.  The curator of this project, Professor Res Ingold explains, "In our case, it is an artistic project with scientific backing."

Founded in 1992, the Art and Exhibition Hall of the Federal Republic of Germany has played an important role in the community of Bonn, Germany.  Designed by the architect, Gustar Peichl, the building displays various exhibitions in fields of art, archeology, cultural history, science, and technology.  Aside from exhibitions, the community center frequently hosts symposiums, conferences, performances and concerts.  One of the more attractive aspects of the building is the intensive rooftop garden, which is often site for sculpture displays.  This vegetated rooftop is a nice addition for relaxing with a fantastic view of the surrounding city.  In the summer refreshments are served at the beer garden, wildflowers brighten the landscape and the air is busy with buzzing honeybees.  Multiple honey bee colonies call this rooftop garden home.  In 2012 these little magnificent creatures produced 1,200 pounds of honey!  Accurate daily monitoring of the productivity of the honey bees is accessible online in German, French and English. 

Green Roofs on the Move

Green Team at Green Roof Technology, - Tuesday, January 29, 2013


By Jörg Breuning

Well before modern green roof technology started in Germany in the 1970s, I was already collecting Sedums in the Alps.  As a kid I liked the little ‘fir trees’ because I was able to carry them home in my stuffed Lederhosen pockets and miraculously they would survive, even after a 4-5 hours hike.  Forty years later, there is still one surviving ‘fir tree’ growing out of a terra cotta pot at my Mom’s house. The last time it was repotted was more than 20 years ago.

When I was a teenager, Professor Hans Luz, a Landscape Architect from Stuttgart, Germany, was pioneering the implementation of green roofs on buildings and parking structures.  A visionary, Luz recognized green roofs’ stormwater retention potential and their overall ability to reduce the environmental footprint of any building.  From there green roofs went viral, spreading throughout Germany and Europe.  It was not long before cities began realizing the relief green roof provided to their overloaded combined sewer systems.

By the nineties green roofs had spread all over Europe.  Pockets of green roof believers had developed in cities across Europe.  But modern green roof technology was struggling to spread beyond the borders of the EU. 

During the nineties I frequently vacationed to the United States, notably the Southwest.  Even while on vacation one part of my mind was always considering how green roofs could be introduced to the States.  I desperately tried to make presentation about green roof in the USA but associations like International Erosion Control Association were never interested.  I talked to many American landscape companies during my vacations, but they simply thought I was crazy.

In 1999 Chicago’s Mayor Delay visited Germany and saw a green roof for the first time and decided he wanted this technology on his City Hall.  Almost 30 years after green roof technologies were first developed in Germany the time was finally right for the United States.  I am proud that I brought green roof technology to this project in Chicago.  

Twenty years from now I believe green roofs will be a fundamental part of all new buildings, as important a basic building feature as windows, doors, heating and cooling, water supply, etc.  In the end it is all about reducing the footprint of a building and putting on top of a building what was once on the ground – this is just common sense.  In my opinion it is simply our responsibility that we have to diminish our impact into nature.   We can do it in many ways, but green roofs seem the most efficient.  The longer we wait the more of our current profit and wealth we have to sacrifice later.

Success also means Green Roofs must be done right the first time.  There is no need to over engineering, use irrigation, strive desperately for LEED points, embellish the aesthetic design or embrace crazy environmentalists’ ideas that want green roofs to save the entire world.

This reminds of another success story that started in Stuttgart, Germany when Gottlieb Daimler (Mercedes-Benz) invented the world’s first car.  His invention went around the globe in a very short time and is the basis of any functional economy.  From the same place, green roofs are now starting to go around the world and will be the basis of any functional urban ecology.


A Nice Gift for Green Roofers - Un Jardin sur le Toit – First Green Roof Fragrance

Green Team at Green Roof Technology, - Monday, January 14, 2013

Un Jardin sur le Toit – First Green Roof Fragrance

by Jorg Breuning

Jardin sur le Toit by Hermès features a little slice of nature perched on the rooftop of the building of the house of Hermès in Paris, France. A feast for the sense and the mind. A fragrance of light and delight, crunchy and cheerful.


Hermes launches the new fourth fragrance from the collection of garden-inspired fragrances Un Jardin, named Un Jardin Sur Le Toit or “A Garden on the Roof” in 2011. Un Jardin Sur Le Toit refers to the especially luxurious garden located on the Hermes’ headquarters building roof. A secret roof garden, hidden in the heart of the city, in Paris.

The garden is full of aromatic herbs, flowers and fruits whose flavors vary as they pass through the metamorphosis induced by the seasons. Its fresh and sweet-smelling atmosphere is captured by apple, pear, rose, green grass, basil, magnolia and compost notes.  This fruity, vegetal, floral eau de toilette is appreciated by both women and men.

The composition is designed by Jean-Claude Ellena.


A Flower in Disguise

Green Team at Green Roof Technology, - Wednesday, January 02, 2013

By: Jörg Breuning & Samantha Yurek

"A weed is a plant that has mastered every survival skill except for learning how to grow in rows." - Doug Larson


Photo Jörg Breuning, Green Roof Service LLC: Hieracium aurantiacum, Orange Hawkweed. Haunted by environmentalists and often branded as obnoxious, farmers and nurseries stamp Hieracium as invasive.

It is all about perspectives, experience and evolution.  Weeds are typically plants growing where they are in competition with cultivated plants or simply unwanted by humans.  However, seeing it from a philosophical point of view any organism has a right to exist.  It is the intention of each organism to multiply, spread and adjust to the surrounding environmental conditions.  This adamant approach has also helped humans to develop and thrive over ten thousands of years.  The word native has become a stereotype of certain plants that should be growing in a particular region.  But with human perspectives being far from uniform, the term 'native' has been skewed over time.  The term is irrelevant when looking at the larger picture of evolution.

An unwanted plant on intensive green roofs could be ideal ground cover for un-irrigated extensive green roofs or vice versa.  Being an outside element, green roofs will undergo natural succession and evolution as described above.  This succession can effect the function of a green roof in the long run for the better or worse.  Ideally, maintaining a green roof helps to guide the plants in a stable coexistence with minimal succession, creating little maintenance.  In most cases it doesn't matter whether the green roof plants were planted intentionally or not.

Un-irrigated extensive green roof designs tend to have extreme conditions; therefore the plant pallet is rather narrow.  It is very difficult for most plants to sustain themselves over decades.  Introducing many of these so-called 'weeds' on to a rooftop environment may prove to be more efficient because of the vigorous growing capabilities.  Yet many factors such as unique weather events during the establishing phase (3-8 years), artificial irrigation, pre-grown nursery trays, excessive fertilization, can be counterproductive in modern green roof technology.

Baltimore County Realizes the Need for Green Spaces; Preserves 38 Acres

Green Team at Green Roof Technology, - Wednesday, December 19, 2012

By: Ryan Miller 

Baltimore County has announced that they will preserve 38 acres of publicly owned forested land in Perry Hall.  County officials believe this to be the largest preservation of open green space in that community in more than a decade.

With Maryland passing House Bill 987 earlier this year, many local governments are looking for ways to minimize the storm water runoff impact on our local watershed.  With increased urbanization, our green spaces are shrinking and so are the vast environmental benefits that come along with it. land will be protected from development and it at two locations: about 8 acres in western Perry Hall and nearly 30 acres north and south of Indian Rock Park.  In an announcement of the land reclassification, County Councilman David Marks said he had worked with County Executive Kevin Kamenetz for the past year to preserve the land.

"Not only are we protecting green space in two distinct regions of Perry Hall, but we are preserving an area larger than the acreage at Perry Hall High School," said Marks, a Republican from Perry Hall. "It is a milestone for the Perry Hall community, and it comes at almost no cost to Baltimore County's taxpayers."

Source: The Baltimore Sun

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