Plants for Green Roofs in Florida

Wow. I drove to Tampa from Jacksonville this week and witnessed first hand the damage last week's twenty degree F temperatures did to horticulture across the state. We must all remember that even south central Florida may be subject to hard periods of cold, freezes and frosts.

Balance. The word that kept popping up in my mind was 'BALANCE'. In designing a green roof for Florida we must keep in mind the 5 H's (they have grown to five from my initial three) - Hurricanes, Heat, Humidity, Heavy Winds and Hard Frosts.

Choose your planting scheme to include three components!

Number One - use the standard green roof plants that survive no matter what. These include plants that come through hard freezes and boiler-type humidity periods. There aren't many of these but there are a few...

Number Two - Select some of the Sedums that will thrive in the winter. They will limp through the summer though. Their poor summer performance can be offset by Number 3.

Number Three - Select those plants that thrive in the summer monsoons but limp through the winter.

A good green roof plant designer will be able to deliver year-round color and interest.

Remember - we focus on non-irrigated Extensive Green Roofs. Roofs that are light weight - no more than a couple two or three inches think.

Florida is tough on Green Roof plants.

Hands on experience through many years or trials is what will produce the best design for each Florida location.

Happy Green Roofing!

Kevin

Florida Green Roof Project Continues with the addition of more cold tolerant yuccas....

The New Florida Green Roof Project is moving forward! We've added several new cold hardy varieties of Yucca! Stay tuned for more pictures!

Hard Freezes and Florida Green Roofs - Winter (Hard Freezes - one of the many 'H's GRs face in Florida)

Judy and I have been scurrying most every afternoon to cover plants as temperatures have been dropping into the twenties here in Jacksonville. Looking at the Weather Dot Com it appears that around Tallahassee the mercury has hit the low twenties several times. Walking by our green roofs, I look up with frost blanket in my hand and want to climb up and cover the plants. But I don't.

Our green roofs serve as our best trial panels as we've said many times before. I have finally reached the confidence level that allows me to know the plants will survive. Still though, many of the plants on our green roof are hard to find varieties and the cold north winds are desiccating, unrelenting and potentially fatal to humans, animals and plants.

I am always proud the next day to see the plants stand straight and soak up the sun's warmth. Balancing the choice between those plants, like the sedums that can tolerate extreme cold but melt in the fierce pressure cooker like humidity laden summer heat - and the succulents that can take the tropical heat but not the cold has been the key to success.

There are not alot of plants that fit into the category of withstanding both of the above limiting factors. Then you add long periods of drought and long periods of innundation to the model as inputs and the list of plants that will survive shrink even more.

Finally add the requirement the plants must still look good and not be dormant to the above and the list really becomes small....

So as I await days light to see what damage, if any has been done and add the findings to our resource base - I hope the coldest night so far of 2009 will produce the same positive results as those before.

Happy green roofing in Florida!

Green Roofs - Another Volunteer Vegetated Florida Roof

Walking the streets of almost all cities and towns you can see plants growing in the toughest of places.

They grow in the cracks between the concrete in the middle of the busiest streets and interstates. They grow up walls, peaking from the tiniest of crevasses. The grow in gutters and in roof seams. Give a plant a chance and many species will grow just about anywhere there is a little sunlight and occasional water or moisture.

The philosophy we carried with us over the years of experimenting with how to successfully grow plants on roofs was simple. It was based on watching plants grow in the most inopportune places.

Our goal was to design a vegetated or green roof that inherently had the following characteristics: 1. Low weight, 2. Reasonable cost, 3. Leaves and color all year, 4. fire resistant, 6. heat, humidity and hurricane resistant, 7. Florida Department of Community Affairs approved, 8. treats stormwater, 9. provides habitat for wildlife, 10. was low maintenance, 11. could be used on slopes (we can go vertical), and finally - a roof that would last - season after season.

We believe we have developed what we set out to do!

Call Judy at MetroVerde - 904-294-2656 to find out more about your new green roof!

Green Roof Plants Bloomin! Florida Green Roof Project

October is a great time of the year for Green Roof Plants! Many of the species with flowers of a red hue are blooming! Email Judy for your personalized roof!

Florida Green Roof Project - Green roofing at dusk...

The plants are under installation. The days are getting shorter. The nights cooler. It hasn't rained for a week and the only water the plants are receiving is the blanket of heavy morning dew.... This weekend we should make good progress with finalizing the plant installation!

Another Green Roof Video - Florida Green Roof Construction

See Previous Post for more on installing a liner on an existing roof in preparation for a new Green Roof!!!

Enjoy the Video!

The new Florida Green Roof Project - Next Episode - Installation of the Liner!

New eUrbanism! Green Roofs everywhere! We are refining the available technology - now doing things only dreamed of before.... So we'd like to think.. Our ancestors and those before us had vertical green techniques so much more refined - even though they lacked the polymer and synthetic materials we have today...

Hanging Gardens of Babylon! and also check out Wikipedia's write up...

IFAS at UF has a great virtual field trip website that provides more info on vertical crop growing and hydroponics.... see previous blog...

OK but back to the new vegetated roof. Today was the 20 mil PVC liner installation day and unfortunately it was real windy - a front is coming through -

Normally on a TPO roof there is no need to put a root barrier down - you always can if you want to but the TPO and the PVC root barrier are one and the same material practically and you end up just duplicating efforts.

But hey! If you want another liner over the TPO - put one there. The black pond liners you can find a Lowe's and Home Depot work great!!! These come in various stock sizes. You can get 13' x 20', 13' x 10', 8' x 10' and others. Watch Craigslist for great buys on pond liners as there are many people who buy the liners thinking they will get a 'round-to-it' and build a backyard pond. It is amazing how many pond liners I see for sale on either e-bay or Craigslist!

For sure you would want to put a liner over asphalt shingles - as we are doing here... Otherwise the roots would devour the asphalt shingles eventually...

But over TPO - well - if you are in doubt build a trial panel! See for yourself!

So since we have a asphalt shingle roof on this project - we are installing a PVC liner. (Always follow OSHA safety guidelines when working above ground)...

Folded up, PVC is heavy and will stay put on the roof. Unfolded the liner is like a waiting sail, ready to leap into the air and follow the breezes. Moreover, liners are slick, slippery and a fall hazard on the ground and especially on a roof or raised platform!

Even over rough - friction heavy asphalt shingles, PVC liners will 'slip and slide'!

MetroVerde's belief is that any vertical penetration through a roof will cause a failure or maintenance issue, sooner rather than later, in Florida's harsh environment!

Today's project roof has a 5/12 slope - moderately steep slope...

And today was WINDY! With the front coming through, as soon as I started unfolding the liner - the wind would pick it up and throw it down over the edge...

See the photo's...

But using MeroVerde's patented attachment system, once you get the mat laid out in a roughly positioned posture - then quickly attach the mat and the roof with the first fastener - usually the highest corner in the direction of the prevailing wind.

Install another fastener ever three feet on both the x and y axis. Carefully move across the roof area, installing all fasteners until the entire liner perimeter has been attached to the existing roof. Make sure the liner is stretched tightly across the roof and there is no obvious buckling or 'air bubbles' in the liner.

Usually the weight of the liner will press down and form against the existing roof. Once the MV GRP vegetated panels are installed the weight should be easily sufficient to hold the entire system in place.

See the photos! The final installation photo shows the liner stretched and attached - ready for the mats!

Watch for the next episode! Until then - Happy Green Roofing! - PS - Feel free to call me anytime you wish to discuss Green Roofs! 904-294-2656... :) Kevin

Brown Curly Q's on the Alliums. It has been a while since we've had a rain event...Florida Green Roofs

Other than the tale tell sign that the alliums are aware that it has been a good while since rain has moistened their roof top beds, the MetroVerde Extensive Green Roofs I've been following are looking good.

The Semps have really enjoyed the respite from the humidity and are looking perky and green! Though you do not see them here. I'll post a pic of them tomorrow.

I was out most of the day today taking the International Society of Arboriculture's certified Municipal Arborist exam - I thought it was a hard test - but as I was reviewing the questions, several key phrases jelled in my mind about adding small trees to the MV Extensive roof panels and after consideration all afternoon - I think it will work!!! But of course, as always, we will vet in the field through many tests. Please be sure and stay tuned for more info as the field trials take shape.

Back to the alliums in a second - but first - we are going to develop a spreadsheet for the blog that will allow us to post temperature readings of on deck asphalt, on deck vegetation, below deck asphalt and below deck vegetated sampling points on a set of Jacksonville, Florida roofs. We will keep the readings posted year around for our interests and comments. Right now I am seeing October mid-day below deck under asphalt readings averaging 128 degrees F while below deck under extensive vegetation mats of 81 degrees F.

We are also running LC-50 tests on straight rainwater and then rainwater runoff from an asphalt shingled roof and a vegetated roof. It looks like the only roof that doesn't kill the fathead minnows is...well - we need to wait for the final data.

OK alliums. As you can see in the photo - the alliums are feeling the semi-drought. Though only a trained eye would probably see the stress indication in the leaf blade tips - it is there. But this is how alliums respond to drought. We will keep posting pictures until we experience a decent rainfall event. Never fear for these plants though - they are tough, tough, tough. Judy and I have worked with these plants for years and years. You cannot kill them and when you trim the blades back you can almost see them grow back out!

Can you tell from the photo? Lots of lush green - but look for the thin brown tips. It has been three weeks since a solid rain. If this was a roof with a modular tray system - here in Florida my bets are that you'd have a dead mess. Mat systems are so much better suited for the three Florida H's - Hurricanes, Heat and Humidity...

Until tomorrow! Happy Green Roofing Dreams! Kevin :)

New Florida Green Roof Project - THE MAT !!!!

One of the basic principles of a successful green roof is the base mat. Mats are the preferred green roof base system for Florida Green Roofs - as we have discussed countless times before here. The reason is simple - the roots in plants secured in trays or modular components eventually reach the tray walls and begin to circle around, eventually strangling themselves to death - remember going to the nursery and buying pot or root bound plants - they did not live long....

Welcome to the mat episode...the mat was delivered today! We will unroll it, flatten it out and begin adding the expanded clay, other non-organics and the tackifier (agar based). Sound complicated? Naw.... Watch for the next episode - to be posted later tonight after we do the above tasks! Happy green roofing - - Kevin :)

South Facing Florida Green Roof Project

We will be documenting an approximately 1000 SF green roof project here on the blog - beginning with the initial mat plantings in October 2008.

The mat material is ordered, scheduled for delivery within the week.

The organic seed stock and cuttings are established and ready for installation in the mat system.

Over the course of the next several posting you will view the current roof (asphalt shingles), the liner and liner installation, the mat and mat fabrication and construction and the final product. Feel free to post questions and suggestions! Join us on this project!



Kevin, Jincy and Ruairi

The 3 C’s of Sustainability: Communication, Community Involvement, and Campus Environment," the 3rd Annual Campus & Community Sustainability Conferenc

This conference, held in Orlando will be a premiere event to attend if you are interested in learning the details of Sustainability and Green Roofing in Florida!

Visit The 3 C’s of Sustainability: Communication, Community Involvement, and Campus Environment," the 3rd Annual Campus & Community Sustainability Conference hosted by the University of Central Florida and the Council for Sustainable Florida website for more details.

I will be moderating a panel discussing the Importance of Restoring Green to the Urban Core and will be joined on the panel by Dr. Marty Wanielista, P.E. of UCF, Catherine Burkee of Breaking Ground Construction, and Rob Overly of Rink Architecture. We will focus on the big three benefits of Restoring Green to the Urban Core: 1- Treating Stormwater, 2- Providing a Sense of Place, and 3- Recreating Habitat for Wildlife.

Examples of Dr. Wanielista's Green Roof systems and more will be discussed.

Join us for this fantastic opportunity to look at Green Roofs and More!!!

How Much Should A Green Roof Cost? and more Green Roofs for Florida musings

One of the most common questions I hear about green roofs & vegetated roofs & garden roofs is: HOW MUCH DO THEY COST? Good Question. Easy Answer.

An extensive evergreen garden roof can be purchased and installed from a base price of approximately $6-8.00 per square foot for simple, one species installations to $12-$14 per SF for a moderately top of the line extensive garden roof with multi-texture, multi-color plan species.

Now, if you have more money than you know what to do with - then you can spend as much as you want per SF. I have seen some vegetated/garden roofs quoted in the $120.00 per SF range (YIKES!!!),

It is educational (and I highly recommend you do this if you are interested in green roofs) to go and talk to your local roofer that has experience with installing TPO roofs. A TPO roof is also a 'green' roof if it is white in color - because it will reflect heat! Usually those roofers who have experience in TPO know vegetated roofs also - but always ask them if their company (or parent company) sells green roofing systems. If they do, be sure to make sure you are receiving unbiased info). A good TPO experienced roofer is Rick Anderson with Delta Roofing in Jacksonville, Florida - call Rick at (904) 292-1592 - tell him you saw his name on Kevin's blog.

Green roofs are my passion, and I believe they are key to restoring green to the Urban Core! - Creating habitat, a sense of place, and resolution to stormwater issues.

Don't be scared off by a quote of $20-$40 per SF for a green/vegetated roof! Those complicated and expensive systems are not necessary!

Please - beware of green roofs that require irrigation. Please!!! - it is easy to grow an orchard on a roof with fertilizer and irrigation and cow manure and etc...

A doubter? Look around the next time you are driving through town at the volunteer plants that THRIVE in sidewalk cracks, overpass retaining walls, uncared for gutters, and more. I've never seen irrigation tubing here!

Now - if you are looking at a global system - greywater, reuse, rainwater catchment (Judy and I are members of ARCSA - check out www.arcsa.org), permaculture - then you may want to integrate recycle irrigation into your vegetated roof - but DO NOT BUY the story that you HAVE to have irrigation. I can show you plenty of applications that have successful and beautiful green roofs that grew up on only rainwater...

OK - want to DIY? email me at chockasacka@msn.com

But before you go and spend $ 20+ per SF shop and compare.

One final tip of the evening. We take and set up light level and temperature recorders on roofs we are evaluating for plant applications. Spend some time to assess what you are working with - this is the first step to good planning.

One last final tip. If you want a top of the line extensive vegetated roof - low maintenance but lush, tropical and beautiful - one that will treat stormwater, provide urban wildlife habitat like you will never believe and create a sense of place your DNA will connect to - email me.

Happy Green Roofing!

Kevin