The Green Roof

For the whole semester, we did a lot work on the roof. At the beginning, we got rid of the weeds of the planters on the floor and the modules on the wall. Some plants are growing well, although some weeds were there. We planted several fruits, like tomato, on the left side of the roof. So far, they are healthy and pretty. 

Two weeks later, we started to make some new modules. Base the amount of the soils, we decided to make 18 modules and separated them into 2 groups first. It was hard to bring such a lot of soil to the rooftop, but eventually, we did it. 

We aligned the modules into two groups by 3×3. Then we filled gravels and soils with different percentage into those modules, for the future research.

I learned how to prepare for planting, it is good to know how many pounds of soils we need/have before we getting started. I have also learned the process of process of preparing and planting.   

 

The Living Wall

It is always good to see the plants which we planted together are growing well.  This semester, we worked on several plantings works from different plant species to different soil types.  By working on the green roof this semester, I learned how green roof and living walls are installed and designed. What a great experience!

The first week, we did some clean works, like getting rid of weeds. Then we had planted a living wall on the right side of the roof. It is a great success. Plants are growing pretty good and flowers are blooming.

Green Wall Assembly

The first step to assemble the green wall was transplanting all of the plants into the green wall module systems.  This took the most time for us to complete.  To transplant we took put some soil in the module then we packed in the transplant plug and topped it off with more soil.  Then at the top row of each module we added some fertilizer pellets.  We only added them in the top row because the irrigation will run the fertilizer through the rest of the module.

After we finished transplanting all the modules we lined them up for assembly.  The plan was to create “drifts” of different plants to make the finished wall a coherent design.  After this we put the modules up, and finished the wall.

Before

After

 

Green Wall Teardown

We started off taking all of the modules off of the existing wall and cleaning them out.  There were lots of cockroaches and spiders in the existing wall.  We found 10 cockroaches and more spiders than we could count.

After this we cleaned out all of the modules.  We placed all of the soil and organic matter into bins to reuse on the next green wall.  Then we washed out the modules and lined them up to be used in our transplants.

Green Roof Projects Overview

Projects

Rooftop Garden

The first project we worked on was the Rooftop Garden.  We planted several different common crops in the existing modular system on the roof and wanted to see how they would grow.  This project was overseen by the undergraduate team for the planting phase.

We planted Swiss Chard, Lettuce, Parsley, Tomatoes, and several other plants.

Modular Green Roof

The second project our team worked on was creating a new set of Modular Green Roof sections that we would test.  We had three systems set up, all the systems were set up in the same plastic modules with the same materials, but we changed the amount of soil and gravel in each set of modules.  One set had one inch of gravel in the tray, followed by some filter fabric, and filled with soil.  Another set had three quarters inch of gravel in a tray followed by the filter fabric and filled with soil.  The final set had only a half inch of gravel, the filter fabric, and topped off with soil.  We set up these systems, watered in the soil, then continued on to the major project for the semester.

Final: Over lay grass flats onto soil and gravel and allow then to take root.

Modular Green Wall

This was the largest project of the semester.  We worked on two Green Walls.  One we replaced a portion of the wall, the other we replaced the entire wall.  We dissembled the existing Green Wall and emptied out all of the waste material for two weeks. Then we prepared all of the modules for transplants, and transplanted the selected plants the next two weeks.  After this we organized and put up all of the transplanted modules the final week to create our roof top Green Wall.

Before

Living Wall!

 

The second wall is more complicated. First, we took the modules off from the wall, and we found the soils are very wet, especially the soils on the bottom of the wall. From the right picture, we can see how wet the living wall was. 

Then we put the modules on the floor and clean them one by one. It was not very easy to wash those modules. Later we put soils back to those modules and planted new plants into modules.

All done! I learned about the ecosystem, planting design, and construction of living wall from this work.

Final Results

The last project we wanted to complete was re planting one of our green walls. Over the course of this semester we have successfully unweeded already established beds, other sections of our green walls have already been replanted, while we also produced new sections of green roof bedding for further study.  As we come to a close, we will discuss the stages we went through and what I personally took away from the over all experience.

This slide show runs a series of photos that were taken as the construction of the bed was created.

Stage 1: Take down panels from the green wall and empty the plantings from them while keeping the majority of soils in tacked. While we were sponsored more materials, we found it important to save whatever materials we already had, thus making them spread further in the long run.

Stage 2: Provided plants had to be transferred to planting panels. Due to having such a large multitude of plants, we had to make it a priority to get the more stressed plants established as soon as possible. To do this we formed an assembly line that cleaned panels, passed plants into panels with new soil and fertilizer.

Step 3: After two weeks of plantings, we completed the panels. The final step included placing the panels back on to the wall and allowing them to take further root.

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In conclusion, there is still much work to be done. I have learned a lot about the proper processes to consider and what elements play a larger role in the success of green roofs. My initial interest in the subject took root about year ago. The idea to improve the heat index, water quality, and slow storm surge really appeals to me. To add to all of these effects there is also the aesthetic value, by learning more about them I might perhaps be able to apply this to my future work.

Final Week: The Great Wall of Green

Lastly, we were given the task of uninstalling and reinstalling the existing green wall. First, we weeded the invasive grasses to disable the growth onto the new plantings. Second, we took down each module, emptied, and cleaned them out to ensure there would be no weeds for the new plants. Lastly, we installed each module with the new soil, various plant type, and fertilizer. Then, we arranged the wall according to texture, growing season, and aesthetic for an overall successful green wall.

There was evidence of pests within the wall from the over-wetness of the wood, which attracted roaches, spiders, and worms. These are all contributing factors to the positive and/or negative growth to the plants, which cannot be quantified throughout our research. So, we resealed the wall with protectants to prevent this.

Photos: Before, during, and after installation.

 

After

Week Two: We Got Dirt(y)

In week two, we were given the task of creating a new module. First, we hauled a ton (literally felt like a ton) of 50 lbs. of soil bags onto the elevator from the ground floor. It was a long and arduous process and it took a while to figure out a way to methodically do so without over-weighing the elevator. We eventually figured it out.

Once all of the bags where on the roof, we laid out each empty module quartile and aligned them with the existing modules. Then, we filled them up accordingly. The base layer with the fabric followed by the soil and topped with the gravel. This process helps with the movement of water through each layer and the ability to retain at the base.

 

Photo: Soil and gravel installation to each module quartile.

Step 1: Laying out the panels in two different sections to allow later comparison between the two.

Step 2: Lay a higher amount of gravel in one section rather than the other. This resulted in there being more soil in one than the other.

Week One: We Became Farmers

The first class we got right to it. Dr. Jeremy Merrill had already bought an extensive amount of vegetables and herbs that he wanted to develop his research on. He was able to get an array of vegetables such as tomatoes, peppers, squash, pumpkin, etc. that also had a variety of growth patterns and conditions. In doing so, it allowed us to observe the which were inhabitable on the roof and what wasn’t. I’ve learned the proper way to install new plantings by loosening the roots to allow flexible growth and placing them into the pre-dug slots.

Photo: Me shearing and planting Thai Chili Peppers into random modules with different herbs and vegetables.

Green Roof 2016 Fall

I learned about green roof technologies in the first year in TAMU, but I never got an opportunity to get myself involved in the practical learning. This is quite exciting that I can do some real green roof work this semester.

During the past weeks on green roof, we have been working on the removing old plants and setting up for new plants. We have been dealing with multiple types of green roof, including modular tray system and living walls.

Modular Tray

When we were working on setting up the trays, we divided them into different groups based on different levels of water needs of plants we were going to plant. We poured gravels into the trays and used tape to control the height levels of the gravel layer, half inch or one inch. Then we put the filter fabric layer on top of the gravels and filled the trays with soil. Now we are ready to plant the plants!

The Final Plant

As the year wrapped up the green roof was extensively planted. There was a big end of year planting party where we wrapped up the planting for the semester. On the middle living wall many plants were literally wrapped up, in cloth, and placed on the new and improved wall. I hope that the plants survive on the wall, and I think that they have a better opportunity to do so than ever before. A few adjustments were made to the wall to improve it this year, and now more water and sunlight than ever is getting to the plants. This was largely accomplished by trimming a lot of the excess cloth off of the face of the wall. The cloth was absorbing a lot of the irrigation, and then dripping it down onto the ground. The extra cloth also shaded some of the plants, which is especially harmful for a living wall. Since the wall is vertical and opaque the plants only get about half as much sunlight as plants in the ground, and any additional shade only puts plants at a greater disadvantage. In an earlier post I wrote about the current irrigation system’s failure, but it turns out that I spoke too soon. After waiting about 5 minutes I was able to see that the water makes it most of the way down the wall, and every single pod looked to be getting some irrigation.

We also finished providing the roof garden with ground cover, and now it is thickly planted as pictured.

Post #2 Green Roof Remix

On the green roof there were two different sections, One section of pods had been planted as succulent garden and the other section was filled with small brush and grass had been let loose for over a year and formed a “roof prairie”. Just about every plant survived, and this semester every plant was growing. There were even one or two blooms each in the garden, but the succulent garden also had quite a few weeds coming up.  To try to get rid of the weeds permanently we mixed some of the roof prairie modules in with the succulent garden’s modules. This way the smaller prairie plants would cover all the open ground that the weeds were growing in.

The modules on the roof were a lot heavier than I expected, which made me think about the overall effects of a green roof. These modules were not just heavy with dirt, but they had continued to get heavier because of the amount of water absorbed by each one. Each module’s plants and dirt absorb and retain a pretty significant amount of water. The plant, dirt, and other materials were all measurably heavier than when the modules were first planted and just about all this additional weight comes from water. I have always thought that South Texas could really benefit from more green roofs because of this quality. A single green roof can absorb a large amount of water that would otherwise become runoff, which can significantly decrease an areas risk of flooding. I think that flood prone areas like Houston could use green roof implementation to help lower floodwaters. Obviously that is a big statement to make, but spending time on a green roof and getting familiar with what it is made of has made me really believe in the stated benefits of these roofs. The first time I heard that a green roof can reduce a building’s electrical consumption by 50% I thought it seemed a bit exaggerated. Now I can see from taking apart and carrying these modules that the dirt and plant material is a really substantial barrier, that I am sure provides excellent insulation.

Just the growth of the plants alone is extremely substantial. It was amazing to see how strong and thick the roots of some of the prairie grass became. When we took apart a module we saw that the roots had wrapped so tightly around the bottom of the module that the letters of the manufacturer were imprinted into the roots. These roots also tore multiple holes through a cloth that I couldn’t even cut with scissors. I always thought that grass was kind of puny, but this grass was nothing to mess with. Even though this grass was tough it was definitely struggling to survive on the roof, the grass was more grey looking than green, and the roots wouldn’t have been so concentrated on the bottom if they hadn’t been looking for more water. It is defiantly difficult to find plants that can thrive long term on the roof. Even though the amount of soil in each module is far from insignificant, the roof provides a limit that the ground just doesn’t have.

This is how we would empty out the modules

After all the experiences of merging the prairie and succulents together, the roof seems to be doing well, and it looks like for the first time that the weeds are outnumbered by the plants we planted.