Outdoor vertical garden

Alyssa from http://akitverticalgarden.blogspot.com has made a living wall in Washintgon that allows her to grow flowers and edibles such as parsley and lettuce vertically.

Alyssa mentioned that her game plan was to build a vertical wall of dirt then plant it. They had some questions first such as: How would we stabilize it? What will we make it out of? How thick CAN we make it? How will we water it? Where should we put it where both sides of the wall will get enough sun? How can we make it where the wall with not bow out with all the weight of the dirt and gallons and gallons of water? What could we plant that would grow well on the side of a wall? They tried googling it, but couldn’t find any answers because no one has posted about a garden like this before.

Fortunately Alyssa gave a detailed account of what they did. First they set posts in concrete several feet down. The actual wall is built of hogwire with shadecloth layered on the inside. The shadecloth holds in the dirt. To prevent bowing they completely wired the inside. Once stabilized, they added a whole lot of dirt.

Alyssa notes that you don’t want to plant until AFTER the dirt has settled. She originally tried planting while the dirt was dry and just thrown in. When the dirt sunk it threw all the plants and the holes for the plants off kilter. So the best thing is to water it thoroughly and start planting from the bottom. Alyssa says she needed to replant several Parsleys which were swallowed by the wall as the dirt settled.

Outdoor living wall

Building the edible vertical garden
The structure of the wall is built of three things: posts to support the wall, wire (hogwire and chicken wire), and Typar. The posts were cemented several feet into the ground to support the large structure. On each side of the posts, a foot apart, the sides of the wall were erected. After the sides were thoroughly wired to the posts and to each other, the wall was filled dirt.

Planting the vertical garden
It is very simple to plant in the wall. You need three basic tools: a razor knife, a shovel, and wire cutters. I would recommend wearing gardening gloves because the wires can be rough on the hands. Simply cut the wires and bend them back making ample room for whatever you are planting. Then slit the Typar the appropriate size. Shovel out the dirt and gently place your plant inside. Within a few days your plant will begin to grow skyward. It is very exciting to see watch it grow up!

What kind of things grow well on the living wall?
I found lots of things that grow well in the living wall, especially salad greens. Any sort of mustard, lettuce, kale, pac choi, etc. does exceedingly well. I have grown many herbs (Thyme, Marjoram, Oregano, Parsley) and flowers. Petunias are perhaps the best flowers to plant in the wall. They do a great job of covering and flowing. Any climbing vines or flowers are fabulous! Both tomatoes and chard have done really well in the vertical garden.

Outdoor green wall

How to add nutrients
Use liquid fertilizer (MiracleGro) and to pour small amounts into each hole using a watering can.

How to water
A soaker hose at the top. Not much water is needed as the wall generally stays pretty wet. Each plant is watered when it’s planted in the green wall.

Vertical vegetable garden

Living Wall vegetable garden

Vertical vegetable garden

Vertical Garden New York

Matt from http://diygreenwalls.blogspot.com/ has built a green wall in his home in NY and provided lots of details on how he did it.

Greenwall Building Instructions

The frame is made out of 1″ aluminum stock that looks like a trellis/lattice work. Sheets of expanded PVC were attached using rust proof screws. Then 2 layers of moisture retention mat  is stapled on with rust proof  staples. A submersible pump on a timer pumps water up to a tube running under the felt across the top of the wall.

Matt just used one tube at the top, but he suggests having a tube for every 8-10 vertical feet. He used regular flexible clear hose he bought from his local hardware store and then drilled holes in it. (However, if you use an opaque tube it helps prevent bacteria growth, so that may be something to consider when you’re building your wall) At one point the pump’s filter slipped and sucked up some leaves. That made the drilled holes in the tubing clog. Matt says that emitters might have made that process easier and they can control flow which was an issue at first with his tube and he had to balance pressure and gravity.

There is a basin at the bottom of the wall built from expanded 3/4″ PVC.

He planted 3.5 inch plants in slits 5″ wide separated horizontally by 2″ gaps. The rows were 4″ apart vertically and the plants are staggered every other row. He cut the slits in the first layer of felt (only the first layer gets cut), took the plant out of the small plastic pot, stuffed it in the slit, and then stapled around it to form a tight little pocket (about 4-5 staples). You don’t want too many staples in order to avoid inhibiting root growth.

Plant Wall

Living Wall Materials

Frame:

1″ Aluminum Square Stock available at a local hardware store

Cheaper Eco Alternative

FSC Cedar Strips 1″x3″s Cheaper than aluminum and far better for the environment. I’d build my next wall with these.

Surface:

Sintra Expanded PVC Sheets 6mm You really need 10mm, but they didn’t have it so Matt bought 2 6mm ones.

Cheaper Eco Alternative

Corrugated Polyethylene Plastic Sheets 10mm
These are untested, but Matt’s thinking these would work even better.

Fabric:

Moisture Retention Mat MRM14 (100% recycled polyester and polypropylene)

Misc:

Rust Proof Staples 12mm (you may need to tailor the length depending on the thickness of your surface material) These are rust proof not rust resistant. There is no iron in them so they can never rust. Expensive but worth it.

Submersible Pond Pump You’ll need to adjust the pump to the size and height of your wall. This one is a guideline. Matt bought his at a pet store and they fitted the pump with adapters so he could connect it to polyethylene tubing from his local hardware store.

Green Wall

Vertical Garden Plants

Each wall can be setup to provide varying amount of light, water, and nutrients. Patrick Blanc has used thousands of different types of plants on his walls. In theory almost any type of plant can work.

Each wall builder will need to decide how much light, water, and nutrients they want to provide. Here’s a brief overview of Matt’s wall.

Light

Matt has decent light in the room but decided to add some supplemental light from compact fluorescent bulbs. The lights used are just regular lights, not special ‘grow lights’. Matt thinks his plants would survive with out the additional light but the extra light can only help and it makes the wall look nicer. Powerful artificial grow lights are available if you want to grow high light demanding plants. Typically if you’re growing edibles you’ll need lots of light, but regular indoor plants do not need as much light.

Water

Matt waters his wall 4x a day for 10 minutes a day (by drip tube on a timer).

Nutrients

The best way to determine how much nutrients to give the plants is to watch them. Matt has added fertilizer to his wall once in the time I have had it and doesn’t see the need to add more. Matt’s not looking for growth, just for maintenance. There is soil around the root ball of each plant and as the water trickles down the wall it picks up nutrients from the soil in each plant. He’s not adding more fertilzer now because he doesn’t see the need… although he may add more in the future.

In a massive greenwall like Patrick Blanc’s, there are different ecosystems in the wall (the tops of the outdoor living walls get more sun and dry out faster and the the plants at the bottom get more shade and stay wetter) For a medium to small greenwall, the plants are all going to be in the same ecosystem and so you’ll want to pick plants that have similar light, watering and fertilizing requirements.

Here’s a partial list of plants Matt used on his wall listed in order of quantity.

Philodendron 35%

Pothos (35%)

Fern (15%)

Nephthytis (10%)

Ivy (5%)

The study was originally intended to find ways to clean up the air in space.. but the knowledge is very useful here as well.

Indoor air pollution is often worse than outdoor air due to all the chemicals we have in our homes. From cleaners and disinfectants to the VOC’s emitted from carpets and paints etc, indoor air pollution sometimes builds up.

The study showed that many houseplants also remove harmful elements such as trichloroethylene, benzene, and formaldehyde from the air.. plus they’re all removing CO2 anyways.

Three main chemicals are found in your home. Trichloroethylene is used in paints and varnishes, Formaldehyde is used in many building materials and Benzene is found often in paints.

Although all plants help indoor air pollution, some are better than others in absorbing chemicals and removing CO2

You can get most of these houseplants right from your nursery. It’s always handy to have some plants in your home.. but these are some of the best:

• Philodendron scandens or domesticum
• Dracaena
• English ivy
• Spider plant
• golden pothos
• peace lily
• Chinese evergreen

Here’s a couple links to a couple of the studies done by NASA:

Here and Here
The below excepts are directly from NASA.. the first quote indicates how the plants do it:

“NASA’s research with foliage houseplants during the past 10 years has produced a new concept in indoor air quality improvement. This new and exciting technology is quite simple. Both plant leaves and roots are utilized in removing trace levels of toxic vapors from inside tightly sealed buildings. Low levels of chemicals such as carbon monoxide and formaldehyde can be removed from indoor environments by plant leaves alone, while higher concentrations of numerous toxic chemicals can be removed by filtering indoor air through the plant roots surrounded by activated carbon. The activated carbon absorbs large quantities of the toxic chemicals and retains them until the plant roots and associated microorganisms degrade and assimilate these chemicals.”

“The technology of using houseplant leaves for reducing volatile organics inside closed facilities has been demonstrated with formaldehyde and benzene. Philodendrons are among the most effective plants tested to date.”