Four Green Roof Questions With PSU’s Robert Berghage

GG: What is your impression of the green roof market here in the United States in its current form and is there potential for growth?
 
RB:
The market is interesting. There are actually a fair number of players. LiveRoof and some of these other roofing companies are providing plant material to provide plants in local markets. There is definitely a market there.

From a market analysis standpoint, the potential is just astronomical. Whether we ever reach that potential is an interesting question. When you think about the number of flat roofs in North America and the total potential space you could be greening, it’s just enormous. At this point, it’s more of a boutique market as only a small percentage of roofs are being greened. The market is very much in its infancy, but that may change as the pressures continue to mount on municipalities and urban areas.

GG: What are the main drivers of the green roof movement?

RB: The driver in most urban areas is combined sewer systems and combined sewer overflows. If you think about a commercial building in a city, between the parking lot and the structure itself you don’t have a lot of places to put water.

GG: Which of the two green roof systems makes the most sense: the modular or built-in-place system?

RB: The modular systems make the most sense to me. You need to be able to green it off site, like at a greenhouse or a nursery, and put a finished product into place. In areas where a smaller roof or logistics are difficult, those factors are driving the cost of systems. If you talk about the post office in New York City, it’s one of the biggest green roofs in North America. When you talk about these huge structures, then it makes sense to do a garden.

GG: What are the opportunities in green roofs for growers?

RB: It’s in supplying the plants. The thing that really freaks out people when they start talking about these projects is the numbers–for sedums especially. Fifteen years ago, someone who grew sedums as a crop might grow a few hundreds of this species, and maybe 1,000 of something else. And that was a pretty big number for sedums. For a roofing system, if you’re doing plugs, consider that it’s 2 ½ plants per square foot. We have one roof on our campus and that’s 50,000 square feet. So that roof alone has 125,000 plants.

The market is still small. The big jobs call for large numbers of plants. Sometimes, the roofing companies have issues trying to find the numbers of plants they need. There are a couple of nurseries that have done really well at making this a large portion of their product line. This is what they do.

Leave a Reply

6 comments on “Four Green Roof Questions With PSU’s Robert Berghage

  1. Let’s hope that there is a lot of research going into edible crops for the plant material. Sedum itself just hasn’t made it into the food pyramid.

  2. We are a wholesale nursery that grow many types of Sedums as well as other plants that are suitable for green roofs. We’ve been trying to break into the green roof market for several years with no luck. Do you have any suggestions for these companies that need growers of green roof plants? Why does there seem to be a lockout to those of us that grow quality plants? We would be happy to provide material needed for the installers that are not using the trays that are on the market.

  3. I’m very surprised that a green roof expert would choose a tray system over a built-in-place system (in most cases)
    I don’t believe his statement has scientific backing. If there is one, I would like to hear about it.

    Just look at the history of green roofs in the European market. The tray system has pretty much disappeared in the industry.
    I see a place for tray systems in the market. However, introducing plastic trays on a green roof simply doesn’t make much sense to me.

    The cost of plastic is an added cost to the customer while they trays don’t serve a purpose after placement on the roof.
    This is most likely the reason that you don’t see a lot of trays used anymore on large scale projects. It’s simply not price competitive.

    Also, trays do not benefit the health of the vegetation inside the module. Most tray systems are starting to fail due to overheating of vegetation in the summer (black edges of the tray warm up and burn bordering vegetation).

    The State of Wisconsin has so many negative experience with tray systems that they have banned this system from all public projects. (I guess i’m not alone in my standpoint)

    I don’t mean to completely burn the use of a tray system (ok, maybe just a little bit). My point is that we have the luxury of several decades of green roofing experience in the European market. Why not learn from it instead of re-inventing the wheel.

  4. Let’s hope that there is a lot of research going into edible crops for the plant material. Sedum itself just hasn’t made it into the food pyramid.

  5. We are a wholesale nursery that grow many types of Sedums as well as other plants that are suitable for green roofs. We’ve been trying to break into the green roof market for several years with no luck. Do you have any suggestions for these companies that need growers of green roof plants? Why does there seem to be a lockout to those of us that grow quality plants? We would be happy to provide material needed for the installers that are not using the trays that are on the market.

  6. I’m very surprised that a green roof expert would choose a tray system over a built-in-place system (in most cases)
    I don’t believe his statement has scientific backing. If there is one, I would like to hear about it.

    Just look at the history of green roofs in the European market. The tray system has pretty much disappeared in the industry.
    I see a place for tray systems in the market. However, introducing plastic trays on a green roof simply doesn’t make much sense to me.

    The cost of plastic is an added cost to the customer while they trays don’t serve a purpose after placement on the roof.
    This is most likely the reason that you don’t see a lot of trays used anymore on large scale projects. It’s simply not price competitive.

    Also, trays do not benefit the health of the vegetation inside the module. Most tray systems are starting to fail due to overheating of vegetation in the summer (black edges of the tray warm up and burn bordering vegetation).

    The State of Wisconsin has so many negative experience with tray systems that they have banned this system from all public projects. (I guess i’m not alone in my standpoint)

    I don’t mean to completely burn the use of a tray system (ok, maybe just a little bit). My point is that we have the luxury of several decades of green roofing experience in the European market. Why not learn from it instead of re-inventing the wheel.

More From Varieties...
Wave Petunias Team

May 3, 2016

Hot Pink Wave-Rave Van Making Its Way To The Big Apple To Promote Wave Petunias And Pansies

Imagine driving down the road, minding your own business, when you’re passed by two smiling, waving, happy women driving a hot-pink van that’s adorned with petunia and pansy flowers. That’s not something you see every day, but motorists in the Midwest and Northeast may catch a glimpse of the Wave-Rave van this week as Ball Horticultural Co.’s Claire Watson, Product Marketing Manager, and Katie Rotella, Marketing Communications Manager, make their way to a media tour and plant giveaway in New York City. Watson and Rotella visited Cleveland’s WOIO Channel 19 news on Tuesday morning to tell consumers about Wave Petunias and Wave Pansies, and remind them to visit their local garden centers to purchase gifts for Mother’s Day this weekend. Check out this clip on Periscope. After the morning news, the ladies stopped by to visit the Greenhouse Grower staff at Meister Media Worldwide in Willoughby, OH. Next stop: Chelsea Garden Center in Brooklyn, NY, where […]

Read More
National Garden Bureau CAST 2016 Bloggers

May 3, 2016

5 Things Gardens Bloggers And Writers Learned At California Spring Trials

For the second year in a row, the National Garden Bureau hosted five popular garden bloggers and writers on a trip to California Spring Trials. Here’s what each of them had to say about their experience.

Read More
Chick Charms

April 29, 2016

Kelly Norris: Why The Plant Collector Market Is Set To Explode, And What It Means For You

In his latest column for Greenhouse Grower magazine, Kelly Norris says there are more plant collectors out there than we think, which opens the way for the gift plant market to explode.

Read More
Latest Stories
Wave Petunias Team

May 3, 2016

Hot Pink Wave-Rave Van Making Its Way To The Big Apple …

Imagine driving down the road, minding your own business, when you’re passed by two smiling, waving, happy women driving a hot-pink van that’s adorned with petunia and pansy flowers. That’s not something you see every day, but motorists in the Midwest and Northeast may catch a glimpse of the Wave-Rave van this week as Ball Horticultural Co.’s Claire Watson, Product Marketing Manager, and Katie Rotella, Marketing Communications Manager, make their way to a media tour and plant giveaway in New York City. Watson and Rotella visited Cleveland’s WOIO Channel 19 news on Tuesday morning to tell consumers about Wave Petunias and Wave Pansies, and remind them to visit their local garden centers to purchase gifts for Mother’s Day this weekend. Check out this clip on Periscope. After the morning news, the ladies stopped by to visit the Greenhouse Grower staff at Meister Media Worldwide in Willoughby, OH. Next stop: Chelsea Garden Center in Brooklyn, NY, where […]

Read More
National Garden Bureau CAST 2016 Bloggers

May 3, 2016

5 Things Gardens Bloggers And Writers Learned At Califo…

For the second year in a row, the National Garden Bureau hosted five popular garden bloggers and writers on a trip to California Spring Trials. Here’s what each of them had to say about their experience.

Read More
Chick Charms

April 29, 2016

Kelly Norris: Why The Plant Collector Market Is Set To …

In his latest column for Greenhouse Grower magazine, Kelly Norris says there are more plant collectors out there than we think, which opens the way for the gift plant market to explode.

Read More
Pennisetum Fireworks

April 28, 2016

Why Ornamental Grasses Are Great For People In Condos A…

Allan Armitage says breeders need to do a better job of making growers, brokers, and garden centers aware of better ornamental grass cultivars for the increasingly shrinking garden space.

Read More
Andropogon gerardii Blackhawks (Intrinsic Perennial Gardens)

April 27, 2016

Know Your Market When Choosing Ornamental Grasses

Growers have no shortage of choices in the ornamental grass market. Narrowing down the selection comes down to finding the right plant for the right purpose.

Read More
Bee on Bidens

April 25, 2016

Breeders Go The Distance To Bring New Plant Varieties T…

Breeders are meeting the demand for new varieties that perform and sell well by extending trialing to engage the grower community, using advanced technology, and encouraging international collaboration.

Read More
Dr Allan Armitage

April 20, 2016

Growers And Breeders Are Always Looking For A Better To…

While edibles become more diverse, there's one goal that hard-core gardeners and urban foodscapers share.

Read More
Syngenta Pentas

April 20, 2016

Syngenta Flowers Opens Its Perennial Genetics To The Ma…

California Spring Trials 2016 visitors to Syngenta Flowers found the breeder company and its employees happy and excited for the future, in the wake of the announcement of its acquisition by ChemChina. Now Syngenta Flowers is ready to move forward with its breeding efforts in geraniums, pentas, and other crops, and it is opening its perennials offerings to the whole supply chain for a better chance to get those plants to retail.     Syngenta Wants To Revolutionize Geranium Breeding The big news in this year’s trial, says Karl Trellinger, Technical Services Representative at Syngenta, is the change in Syngenta’s breeding efforts in geraniums and pentas. The Calliope geranium series, long considered a premium line in the market, is getting a makeover. Growers have told the breeder that they love the colors available in the Calliope series, but the plants are just too vigorous for smaller containers and combinations. As […]

Read More
Petunia Vista Bubblegum (Proven Winners)

April 20, 2016

Proven Winners Funds Gardening “It Couple,” Names Plant…

Since 1992, Proven Winners has been changing the gardening game, and it’s not stopping now. With new plants, improved series, and interesting retail customers, the brand aims to make planning easier for growers, and make gardening easier and more fun for consumers. At its new 2016 California Spring Trials location at Kirigin Cellars in Gilroy, Proven Winners had the space and a beautiful setting to lay all of its offerings out, from new and improved varieties in annuals, perennials, and shrubs, to marketing and retail programs. Check out the slideshow below for highlights.   Proven Winners Is Flexing Its Marketing Muscle One of the ways Proven Winners is working toward better use of its products and gardening in general, is by supporting the gardening authorities that gardeners of all ages trust on social media. Director of Marketing Marshall Dirks says while searching for influential gardeners, he came across a young […]

Read More
Scaevola 'Purple Haze' (Danziger 2016)

April 19, 2016

Allan Armitage Picks His Favorites From Proven Winners,…

From “crazy” petunias to container pentas, there was plenty that caught Allan’s eye during the final day of 2016 California Spring Trials.

Read More
CallaFornia Red

April 19, 2016

Golden State Bulb Company Shows Off New Concepts In Cal…

There’s no question that Golden State Bulb Company’s specialty is in breeding virtually any color of Calla Lily, available in about any habit — cut flower, bouquet pot, upright pot type — the list goes on. But now, the bulb specialist is focusing on making calla lilies more accessible to the masses, for use in combination planters and the landscape, with calla six-packs. Calla breeder Peter Beckman showed us the shrunken-down version of these beauties, and they’re certainly perfect for patio pots, planting along paths or at the front of the garden, or en masse for an elegant statement. This presentation makes it easy for consumers to pick up and use callas, without the intimidation they might feel from a bulb crop, says Dr. Allan Armitage.   They’re also versatile for growers to plant in early to mid-February to add to finished containers in the spring, or to sell in […]

Read More
Disney Trial Garden

April 17, 2016

Mark Your Calendars For Florida Flower Trials In May

The two-day event, which takes place in Orlando, is held in conjunction with the Epcot International Flower and Garden Festival and offers educational seminars, tours, and open houses.

Read More
Dianthus Paint the Town Fuchsia_CJW14 (2)

April 16, 2016

Proven Winners Focuses On A Better Consumer Garden Expe…

Excellent, long-lasting performance, and easy maintenance are at the core of Proven Winners’ introductions.

Read More

April 15, 2016

Pacific Plug & Liner Features Plenty Of New Varieti…

One of the best-merchandised spots on the California Spring Trials is always Pacific Plug & Liner (PP&L), where the greenhouse is stocked with beautiful plants and displays, and the people are dressed to the nines and graciously ready to help in any way.

Read More

April 15, 2016

American Takii Commemorates 180 Years Of Industry Commi…

American Takii, Hilverdakooij, and newcomer HMA Plants show off zombie-zone celosia, new dianthus, and hip succulents.

Read More

April 15, 2016

Ernst Benary of America Takes Plant Fashion Week To The…

Ernst Benary of America gave growers a taste of the fashion world during the new variety promenade held during California Spring Trials 2016.

Read More
Fashion Show At Benary

April 15, 2016

California Spring Trials: Dr. Allan Armitage Notes Emer…

Attractive new varieties will draw the eyes of consumers, but innovation and creativity will keep them coming back.

Read More
Delizz Strawberry packaging

April 14, 2016

ABZ Seeds’ Delizz Strawberry Makes Mouths Water At Spee…

Speedling, Inc. hosted Hem Genetics, Thompson & Morgan, ABZ Seeds, Plant Source International, and Vista Farms For California Spring Trials 2016. Here are some of the highlights of the trial.

Read More
[gravityform id="35" title="false" description="false"]