Having said that, probably like you since you’re reading this, when I do the research I want to buy as direct as possible.  But believe me when I say: make a conscious decision not to use a Landscape Architect for larger projects because you WANT to go through the learning process, or because you have already been through the school of hard knocks, not because you want to save money.  Mother nature is miraculous for making overwhelmingly complex systems naturally simple and available.  However, an extensive container garden or green roof is a totally artificial environment vs a back yard.  You are trying to mimic nature and chances are that over the long run you won’t save money on larger projects.  I don’t want you kicking yourself later.  There, somebody had to say that.

As in back-country powder skiing and mountain climbing, you don’t get all the information from a book.  It takes years of experience to understand local conditions and seasonal changes to stay alive. The same is true for your plants.  When property owners and “retail” customers of DeepStream Designs contact me about large planter projects directly we make a conscious effort to direct them to at least consider the services of a Landscape Architect.  Believe me, if you have even a medium-size project, the slight mark up they may put on products in addition to their fee is money well invested if you, or your project, are the type that can’t live with expensive and time consuming false starts.

This article is dedicated to those who think it is best to understand the costs and benefits of  advanced drainage system alternatives before installing plants in containers.  For those of you who have not had the benefit of  walking the trade show floor at a Landscape Architect conference, or who did so without this aspect in mind, I will introduce high-tech alternatives that I am incorporating as options into planters I design for DeepStream Designs.

As a Developer and Property Manager who has had to deal with drainage problems in large containers and at properties with lots of medium-sized planters, I can tell you it is an expensive, time consuming, and demoralizing task to deal with poorly draining planters that ultimately have to be dug up and remedied.   

As prevalent a role as solar gain-induced thermal shock to root systems plays in stunting or killing container-grown plants, drowning them is even more prevalent, at least in rainy climates.   Water-soaked roots can kill a plant in less than 24 hours, whereas baking and steaming roots in a single-wall planter or pot can take weeks, or even months, before the plant finally succumbs. 

Here in Florida, storms can dump 6″ of rain in just a few hours, so it is easy to overwhelm a poor drainage system and you can literally see containers overflow the top.  However, long periods of drizzle and gray sky, conditions found on the west coast, combine low evaporation with soaking soil which also subtly builds up fatal water levels in containers without an effective drainage system.  

The primary reason for water build up is a malfunctioning watering system combined with a drain clogged by dirt or roots, not too small a drain.  Given that a planter filled with nothing but water 6″ deep will drain at the rate of about a cubic foot per minute through a 3/4″ opening, no amount of rain alone will overwhelm a properly functioning planter drain.  Single-point drains of this size are convenient to use for inconspicuous controlled planter drainage systems on balconies, roof tops, and courtyard patios.  The key to making this work over the long term is technology and design.

Proper drainage is the element that the container industry is least likely to talk about because it is relatively complex and is not readily “packaged” for sale.  Making potential customers of larger pots and containers aware of drainage issues is seen as a negative sell, so it is brushed off with instructions to “Drill a couple of more holes in your pots.”   This is an area in which I believe DeepStream can bring great added value to its customers.

With that said, the advice to drill more holes falls into the “Just because they said it doesn’t make it not true” department.  It is in fact the most cost effective approach for smaller, easily re-potted plantings that you can lift out, in pots which slope evenly outward as the pot wall moves towards the top.  This simple classic form facilitates the removal of the plant to clean out blocked drainage holes without damaging either the pot or the plant.  Essentially you are pre planning for blockage by increasing the size of drains that will be clogged.

When considering drainage for larger planters, and which planter forms to purchase, the first step is drain location:  Realize:  YOU WILL HAVE TO DIG UP YOUR PLANTERS SOMETIME! 

Yes, that’s the dirty secret.  It is inevitable.  The question is how long can you go between major events.  Does 10 to 15 years sounds good?  Then  read on.  Even though drainage issues can often be fixed with the plants in place if the planter liner is properly designed, as DeepStream’s are, it is much more convenient to avoid them, and less costly over the long run as well.

If you have read the Blog article on Planter Design, or looked in-depth at the DeepStream Designs’ website planter section, you may remember that the reason I ended up designing free-standing planters was to avoid the structural problems associated with built-in planters:  waterproofed planters built into buildings with poured concrete will at some point succumb to settlement cracks,  as well as drainage issues.  Even the best sprayed, rolled, or troweled on concrete liner systems I have seen will leak at some point in time and digging in them doesn’t help. 

So if you have plans for specimen plants, or are planting trees that will grow too large for workers to lift by hand, make sure you have crane access to lift the trees, or some way to get fork lifts or other types of equipment like tripods in to lift the plants out of the planter for repairs, or to bring in new ones should major plants die.  Avoid building, or buying, planters with drains in the bottom where you will have to remove large plants to get at them.  Install a vertical 2″ PVC pipe up to the final soil level, with a removable top to keep soil out, before filling the planter with soil so that you can pump water out in an emergency before the plants drown.

When considering free-standing planters, and larger planter liners hidden behind a decorative facade, keep them small enough to work on.  Break the planted area up using multiple overlapped liners, rather than one big liner with one point of failure and lots of plants to remove to find the problem, or to die in the event of a catastrophe.  It is not just the cost of the plants to consider but also the considerable disruption and effort to find and remedy the problem.  There is also the mess to clean up and the potential for cosmetic damage to the building by workers during the process.

The second step in drainage is starting with the right soil mixture, both for the plant as well as the building weight limits, as we often find on rooftop and balcony projects.  You are looking for soils that will hold nutrients, PH, and moisture within fairly specific ranges that best suit what is being planted, while at the lowest possible weight.  Very seldom is “dirt” just dumped into a container.  This soil selection process, done right, eliminates much of the problem caused by “fines”, the small clay-like particles that block filter membranes.

The third consideration is filtration and root blockage.   A planter is really just a shaped French drain.  Small particles of clay, fines, are carried by the gravity induced water flow downward towards the drain.  Unfiltered, these fines will block any filter membrane in a remarkably short time.  The standard way to create a rough filter well area is to fill the bottom of a planter or pot is a few inches of gravel over a bottom drain.  One of the key design factors of the DeepStream planters is that it uses a liner, within a decorative facade, that not only prevents solar gain but also hides drip irrigation lines and the drain.  This is important in aiding filtration because the drain does not need to be limited to the bottom of a pot.

DeepStream’s liners locate the standard 3/4″ drain a couple of inches up the sidewall creating a “well” below the drain.  Fines tend to settle down into this “well” as water flowing towards the sidewall drain tends to be very slow under most circumstances, so most fines gradually work their way to the bottom.  The well also acts as a small water reservoir for the larger roots.  DeepStream’s standard drainage system includes a 12″ by 12″ drain board, think of a thin  uncrushable egg crate covered with geo-textile covering, to increase the drainage surface area.  The drain board comes hot melt glued over the drain.  Additionally, there is a roughly 2 sq ft piece of weed block fabric to be folded over and placed over the drain board as further protection against penetration by roots.  

Weed Block, as geo-textile is often marketed as,  is a misnomer.  The “30-year commercial landscaper” variety you see at the large home centers will have roots growing through it in less than 2 years.  That said, it still helps delay the inevitable and DeepStream still provides it with the standard drainage kit.

It is highly recommended that the geo-textile fabric is kept in place by the very important filter of at least 2″ thick covering of very clean, very coarse sand of between 1 and 2 mm particle size.  For reference, the wire of a medium paper clip is 1 mm.  While very coarse sand is hard to find, it is the best filter although it does nothing to block root penetration.  Masonry or playground sand is too fine and will compact and prevent drainage, pea gravel lets too many fines through and they will block the filter fabric.

Technology Enhanced Filtration:  Two Steps

The most important aspect of new drainage technology is in preventing root blockage.  DeepStream now offers an optional  root control fabric, BioBarrier (TM) with a plastic-embedded non-systemic herbicide with a lower toxicity than table salt or aspirin that creates a 2″ thick root deflection zone around the drainage material by preventing root cell tip division.  The product, guaranteed effective for 15 years, has been used as a weed control system for more than 35 years in agriculture to prevent weed growth between row crops.  Now, with proper filtration, it should be able to go 15 years with out digging up a planter, usually a job performed every 2-3 years in heavy rainfall areas.

Giant sports stadiums and golf courses with millions of dollars at stake if drainage fails use high-tech crush proof mats of plastic tubing covered with geo-textile to ensure large drainage area and directed water flow to prevent damage to grass and delays in play caused by flooding.  DeepStream now offers this same advantage in its single-point directed flow system uniquely adapted for balconies, roof gardens, interior courtyards and other areas where drainage control is required.   This is lighter, more effective, and allows for deeper planter medium than less effective gravel systems.

In keeping with DeepStream Designs’ mantra:  ”Reduce, Reuse, Recycle,” I wanted to create a planter and recycling bins with the lowest impact on the environment that I could for our commercial clients that are working on projects striving for LEED certification.

LEED (Leadership in Energy and Environmental Design) is a Green Building Rating System, developed by the US Green Building Council, which provides a suite of standards for environmentally sustainable construction.

L - R: Tropical Hardwood, 3 year old teak, Aged Hardwood

Aged Hardwood, Tropical Hardwood, plantation- grown Lyptus wood planter 18 months old

To that end, DeepStream Designs is now building planters with the same sophisticated design as the Mariner planter using HDPE plastic lumber made from recycled milk jugs.  The LEED Commercial Collection is a no-nonsense “set and forget it package” perfect for restaurants, commercial installations and residential projects where minimal maintenance is as important as aesthetics.

As with all planters, the plants themselves help cool the earth,  cleaning the air by producing oxygen as they convert and trap carbon.  In addition, the Commercial LEED Garden Planters I designed for DeepStream reduce man’s impact on the environment because:

• It’s RECYCLED and RECYCLABLE!

- Using recycled plastic “lumber” planks eliminates the cutting of trees and uses far less energy to ship and manufacture.

- The plastic lumber DeepStream uses is made from recycled post-consumer HDPE (high-density polyethylene) from milk jugs and other polyethylene packaging that might other wise be destined for landfills.

- The planter and recycle bin liners are also both made from pre-consumer LDPE ( low–density polyethylene).

- Aluminum legs and straps, along with plastic components are 100% recyclable.

• Maintenance Free!

- Uses no energy, chemicals, or materials to maintain.

- Plastic lumber never needs to be painted, oiled, or stained and won’t rot, splinter or split.

- Proprietary extruded legs of 6063-T5  aluminum are finished with a durable etched marine anodized finish and HDPE non-scuff feet.

- Stainless steel fasteners are installed with dialectric paste to prevent corrosion.

- Modular design facilitates easy repair should a product be damaged.   Recycle the damaged piece and receive a replacement piece at DeepStream’s manufacturing cost, using their Core Replacement Program.  Don’t throw away that valuable product!

• Colors won’t fade - Ultra-violet stabilizers used in the lumber ensure colors look as vibrant decades from now as they do today.
• Cost Effective - Working with recycled plastic lumber not only reduces production costs, but it also requires NO MAINTENANCE, reducing the life-cycle-cost of ownership over time compared to wood Garden Planters.

While the plastic lumber I have specified for DeepStream is still full 3/4″ thick tongue and groove planking with a simulated wood grain, and only a few cents a square foot less than natural hardwood lumber, several aspects of Commercial LEED Garden Planters and Recyclers reduce the manufacturing cost without cutting quality so that DeepStream can pass along the savings to its customers:

• Planter Boxes and waterproof liners with drainage are stocked in specific sizes to eliminate waste.
• Planing, sanding, and hand-rubbed finish are eliminated taking hours off of production time and saving energy.

Optional drain attachments with overflow control on the liners allow  planters to be used in any interior or exterior installations.

Planters with liners ship fully assembled, just add dirt, or they can be dissembled for shipping or flat storage in 15 minutes.

Tropical Hardwood Grain

Aged Hardwood Grain

Successful landscaping and gardening on balconies and rooftops, especially of condo towers, has many challenges that residents with terrestrial gardens in homes don’t share.

My goal with this forum is to make the reader/contributor aware of these somewhat complex issues, offer simple, straightforward solutions when I have them, share resources, and garner constructive input from other interested parties so I can continue to help sky gardeners meet these challenges.  Hopefully gardeners can make high-density urban environments not only more beautiful but also more eco-friendly with low-lifecycle-cost, sustainable Gardens in the Sky.

Residential and office condo towers are increasingly prevalent in dense urban and coastal areas and contribute to the formation of “heat Islands” and global warming by adding heat-retaining surface area unless they can be landscaped.  In addition, according to the American Institute of Architects (AIA) , buildings are the leading source of greenhouse gas emissions in the United States. According to estimates in the AIA’s Architects and Climate Change report, buildings represent 48 percent of carbon dioxide emissions, with transportation and industry representing 27 percent and 25 percent respectively.

The Green Roof movement is great, but the ratio of wall to roof area is much greater on high rise buildings. If Architects designed balconies with drainage and water spigots built into their clients high rise buildings, it would make it easier for residents and offices to help offset their impact to a far greater degree both in terms of cooling and exchanging oxygen for carbon and absorbing other pollutants.

When I was developing a condo building in Miami, where my wife and I now live after years at sea, I wanted to create a livable rooftop with lush landscaping. Frustratingly, we were unable to convince the city building department in 2004 that green roofs were insulation in and of themselves, so we were unable to have a grass roof.  I realized, however, that the roof surface area of a condo tower was a much lower percentage of the building surface area than the walls themselves.  Therefore I began a search for large lightweight planters that had a high ratio of surface area to weight to use both on the roof and balconies.

At the same time, I wanted to avoid problems associated with built-in concrete planters located on the roof, such as leaking and creating expensive structural damage to the building. In addition to being immovable, there are limitations on where built-in planters can be located, they are impractical on cantilevered balconies, and they impart heaviness to the building design that I wanted to avoid.

While lots of great looking pots exist, large surface area planters were scarce. Also, as I was soon to learn, pots had serious drawbacks for use up on buildings, especially on sunny south and west facing exposures.  As I proceeded through the sourcing process, I eventually assembled a list of attributes that I felt was important in these planters:

· Large surface area

· Aesthetically pleasing

· Variety of dimensions and materials

· Durable, with a low lifecycle cost

· Low impact on the environment

· Lightweight

· Thermal protection for roots

· Drainage control

· Stability in high winds

· Easy to water

Ultimately, I could not find what I was looking for, so I started my own design and manufacturing company to create customizable planters to address all these issues.

www.flickr.com DeepStream Designs

I have found solutions to my issues and, in the process, discovered valuable resources for planters, irrigation systems, and drainage control, as well as some dead ends that I will share. I hope that my readers will contribute their own innovative ideas and experiences in creating a green roof, roof garden, and landscaping a balcony or patio so that we can green up these new high-density vertical neighborhoods sprouting up all over, and minimize our environmental impact.

Be forewarned: I don’t have a green thumb and I almost named my blog “The Reluctant Gardener!” I’m certain that readers/contributors to this forum can add a great deal of sage advice from their own experience when it comes to what works in terms of plants, soils, irrigation and containers when creating a green roof, balcony, or patio. I must admit, though, that I have one of the most vibrant rooftops in our neighborhood, even if I wasn’t able to plant grass and I have killed a plant or two in the process.

All in all, it’s been fun. I find the “Zen” of sitting amongst my plants with friends at sunset or for morning coffee before a long bicycle ride very rewarding. Even if my siblings find the thought of me gardening to be extremely amusing, I still enjoy eating tomatoes and mangos I’ve grown in the sky.

Using the services of a Landscape Architect is highly recommended to shortcut the process of creating a pleasing space integrated with your lifestyle and goals. Keep in mind that, as in any profession, many practitioners have found what they consider to be tried and true practices and may not have kept up with changes in the industry, so you need to be informed. A true professional will welcome your respectful input because the ultimate goal should be your satisfaction. Don’t be intimidated; share your ideas and feedback with them.

You may be unfamiliar with many of the resources I list, as they are sources used by Landscape Architects; however, the quality of products found using these resources are of a professional grade, and thus the impact on the environment, and the lifetime cost of these products is far lower than many “consumer” products that literally define planned obsolescence and a harmful throw-away society.

Challenges and Solutions:

Foremost among the problems I faced in sourcing large planters with substantial surface area was finding any large planters at all, let alone contemporary planters in a variety of styles and sizes that provided protection from soil overheating on south and west facing exposures, water drainage control, stability in high winds, ease of watering, and portability.

Challenges:

Large surface area: Large planters, especially attractive ones, were surprisingly hard to find. While there are lots and lots of pots of various sizes, they really do not provide the large surface area to plant trees, hedges or vines necessary for the shade and privacy screening that I wanted for larger areas and rectilinear balconies.

Aesthetic: Planters that I found with large surface areas looked more institutional or commercial in design and were more appropriate for a parking lot. They simply did not possess the appropriate design attributes of architectural planters for a residential project.

Variety of dimensions and materials: Again, none of the ready-made large planters that I was able to find were available in custom sizes to fit all the niches and variety of areas that I needed planters for. While there may have been a choice of color, there really was not a choice of materials that would impart varying but compatible looks as one finds in pots. In Landscape Architect terms, these large planters fall under the “site amenities” category and are really more appropriate for streets, parks and parking lots.

Each type of material used in construction has its advantages and disadvantages, which vary greatly with construction and design:

· Ceramic and cement are not waterproof and cement planters have steel re-bar at their core. Steel, which expands to 20 times its size as it rusts, cracks the cement, leading to complete failure. If a concrete planter is appropriate for your project, ask the manufacturer to add Xypex® to the mix before construction to retard this process for as long as possible.

Cement planters are very heavy to take up elevators and stairwells, and they are just as much work to remove. You may need a crane. There are some lightweight concrete planters coming onto the market now that may do a better job if they can be adequately waterproofed.

Issues with Cement Planters

The ratio of surface area to weight, and lack of controlled drainage limits large cement planters to the ground.  Light color cement planters of great mass offer some protection from solar gain, although they hold heat well into the night.

Cracks along rebar reinforcing grid

Un-reinforced cement breaks easily.

Planters have no means of drainage control leaving a mess.

Issues with Ceramic Planters

Large ceramic planters have some of the same drawbacks as cement, although thinner walls make them lighter and more fragile, at least they do not have steel at the core.  While they provide some protection from solar gain through evaporative cooling when wet, more than a couple of hours of sun will dry them out.  There are no large surface area ceramic planters that I am aware of.

Ceramic planters should not be painted as they will peel immediately.

· Initially I was drawn to the wood planters you see at street cafés all over Europe, but every planter I saw was falling apart. With my experience in yacht maintenance and rebuilding, I could see that existing wood planter designs were not built to last for decades.

Available wood planter construction techniques fastened wood to wood, and planters would tear themselves apart with the expansive forces that wood exerts through repeated wet and dry cycles.

For centuries, wood dowels have been inserted into holes drilled into rock, then soaked with water. The expansion force of the wood is thus harnessed to crack blocks off marble and granite for construction, even though the blocks are hundreds of times thicker than the thin wooden dowel.

Since every wooden plank is cut from a different part of the tree, it has its own differential rate of expansion and warping when wetted. This makes dimensional stability using standard wood-on-wood construction in two dimensions impossible to maintain over time, and shipbuilding techniques are far too costly for planter construction. In addition, most wood planters lack adequate isolation from the soil and the deck or sidewalk, which promotes fresh water rot.

Issues with Wood Planters

New wood planters constructed by traditional methods.

Traditional construction warping after just a few months, wood feet on deck.

Horizontal to vertical separation pulling fasteners out, panels separating.

Vertical grain splits, warps, & rots

Vertically exposed end grain, and non-tropical hardwood quickly succumbs to rot and splitting, even using heavier bolted construction

Unsupported and exposed liners are problematic and unsightly.

While wood will go grey over time just like your teak garden furniture, unless you spend time varnishing them often, tropical hardwoods have been used for centuries for shipbuilding, boardwalks, docks, etc. If you like the character that time imparts to wood, as I do, a planter constructed using my techniques can last for decades.

DeepStream Designs horizontal planked tropical hardwood planters are constructed without frames, properly isolated from wet decks and soil with properly suported, watered and drained liners.  They can look good for decades.

· Plastic and resin can be excellent materials if the materials incorporate UV stabilizers. High-quality resins should be able to last for at least 10 years, but even then the surface will get chalky over time. Fiberglass can be waterproof if the proper marine resins are used or a barrier coat has been applied, but like resins and plastic it will develop a chalky surface over time. Proper marine resins and barrier coats are very expensive, if a Fiberglass pot is cheap is will not last but just because one is expensive does not mean it is well made. Personally, I really like the ones that incorporate materials such as copper in the epoxy resin so that the patina improves over time.

Issues with Plastic, Fiberglass, and Foam Pots

The major problem with all these pots in a sunny location is lack of protection solar gain, even more than than size, shape, and longevity.

While there are many cheap plastic pots from home stores, I have never seen one large enough to be called a planter, and I can’t resist a word of caution. All of those cheap pots are too thin, contain no UV filters, and they quickly get brittle and break down. Many have painted exteriors that will soon fade and peel. One particular series of plastic pot found at a national home store chain actually has a two-part construction that can fool you into thinking that they are of higher quality than they actually are. After a couple of months, they separate and the thick top rim falls off. Others are constructed of cheap foam covered with other materials, which quickly break down, and fall apart.

Home store chain pots a year old, note the thermal shock to roots.

While ok if shaded, another shortcoming of plastic pots, aside from a short life, is that available pots are too small for larger plants and the taproot grows out of the hole on the bottom, ripping the pot and making it unstable.  Note the surface degradation of the foam core plastic pot, even in the shade.

Just getting some of the plastic and foam core pots from the large home store back home without breaking proved impossible. Their design and construction was totally inadequate, sacrificed in the quest for the lowest initial cost to lure in suckers like me! When I calculate the time and effort expended to select, buy, return, buy, return for credit, and then start the process over again, the cost of that lesson was very high indeed. And that is without all the hassle and mess of planting and unplanting. So much for value at the low end of the spectrum.

More examples:  relatively expensive foam core pots, above, show typical surface degradation in just a few weeks.

Fiberglass Planters

Contrary to popular belief most fiberglass construction is very prone to breakage

While most fiberglass planters are light, at the expense of strength, they may not be durable enough for certain location.  In addition they are almost all single-walled and prone to solar gain. White or light-colored ones would be better in sunny locations.  They do not have drainage control, nor do they hide drip irrigation lines.  The expensive large ones above are installed in Miami’s downtown area and while shaded by buildings, they are not really rugged enough for the streetscapes in which they are installed, nor do they have much surface area.  Believe it or not, these planters are just 1/8″ thick painted skins of chopped fiberglass sprayed into a mold.

Metal planters have various issues depending on the metal and the design.  There are very few large surface area metal planters, and most are forms inappropriate for windy locations. All metal passes solar gain rapidly and is not appropriate on long sunny south and west exposures unless there is a separate liner inside.  Steel, iron and all forms of ferrous metal rust, including stainless steel.  Cast aluminum and bronze can have great longevity depending on the alloy.  Zinc and copper patina nicely, but the seams will soon leak if there is no liner. Again, there are very few large surface area metal planters, as the metal is thin and non-structural.

Issues with Metal “Planters“

Metal planters leaking with rusty seams and rust through pin holes

Thermal Protection: From the plants’ point of view, thermal gain is as deadly as over- or under-watering.  Pots and most existing planters also lack insulation qualities to protect the soil from solar gain. On a sunny 80º day, the sun can heat a dark single-layer pot to a surface temperature of 120º, and on a 90º day, the surface temperature can measure 140º or more, with the soil measuring 110º+ on the sunny side of the pot.

Within minutes of moving this fiberglass pot into the sun the surface temprature climbed to 125 degrees on a 84 degree day, while the “liner within a planter” concept in the planter behind it keeps the soil at no warmer than the temperature of the air.

No matter how much water we gave plants, they didn’t do well. Pulling a plant out of a dark pot I found that the roots were literally being steamed! Unless there is a thermal break between the wall of a planter and the container for the plant, the solar gain is transferred to heat the soil. A proper thermal break will keep the soil no warmer than ambient air temperature and prevent both thermal shock and steaming the root system.

These newly planted palms already show signs of stress in limited morning sun. The edges of the leaves turn brown and over- watering rots the heart out of the palm closest to the sunny side so it is lost.  Sea Grapes are much heartier, but will eventually succumb.

Only true low solar gain Low-E glazing, which is expensive, can block solar gain. Tinted glass is not enough on south- and west-facing exposures.

Even the browning palm (above top) in the ceramic pot, which has some measure of evaporative cooling when wet, suffers heat stress.  The Robellini palm (above bottom) had no chance of survival.  It has lost the two east facing trunks even though the fiberglass pot is in the afternoon shade of the parapet wall.

If you are using a single wall planter in an exposed sunny location and not getting good rewults then try to place it behind a barrier to solar gain as you see in this picture.

Here you are looking south west so the building shades the planters in the morning, then full sun for about 2 hours and then the low parapat shades the planters all afternoon.

Drainage control is important for several reasons:

· If planters do not drain properly, plants drown or develop root rot.

· If drainage is too easy, then water is wasted, which can be problematic when faced with water and/or time restrictions and nutrient wash out.

· Very few condo, converted loft or apartment buildings have drainage built into the balconies for planters or pots. Having dirty water overflow from balconies and run down the side of the building or drop onto unsuspecting pedestrians and autos is usually not an option, and may be a violation of your condo rules as well as local city codes.

Condo Boards and building management are understandably reluctant to let residents have more than a pot or two outside on a balcony that can be brought in when it rains. While rooftops generally have drainage, it’s not usually where you need it, so they too have issues when creating a landscaped or green roof, even on a limited scale.

Drainage that is limited to a hole on the bottom, even covered with drain board and filter geotextiles, is especially prone to quickly repeated blockage that requires a lot of effort to restore.

Ease of watering: this challenge is more complicated than it initially appears:

· First there is the issue of meeting watering schedules imposed by many municipalities, which may include watering at night.

· Watering large planted areas, or a great number of planters, with a hose is very expensive in terms of time.

· Many large planters can be landscaped with plants that have varying root depths.

· Planters that have a reservoir system only water to one depth, so planting flowers or bushes to surround trees is impossible without additional water sources. Even then the deeper-rooted plants can be over-watered and drown without great care in watering and plant selection.

· There is also the challenge of providing automatic watering systems without interfering with the aesthetics of the overall project. None of the planters designs shown above have a way to hide drip irrigation lines.

Low lifecycle costs, low impact on the environment: These two issues really go hand in hand.

Most developers want to create a “look” without costing a lot of money because the object is to sell the residences for the most money while spending the least amount of money delivering that look so that profit is maximized. Resident owners may be limited by their budget but are, in general, looking for the lowest possible cost over time.

Quality almost always delivers the lowest cost over time. A well-made product that costs twice as much, but last three times as long costs less money over time and exacts less of a cost on the environment. It also takes far less effort on the purchaser’s part, reducing acquisition and delivery costs, as well freeing up resources for other uses.

Often the cost of the product is confused with quality. The quality-cost equation comprises not only materials and construction, but also thoughtful design, careful purchasing, manufacturing, distribution, and sales cost. While two planters of equal aesthetic appeal and surface may cost the same amount, to truly evaluate value you need to compare the longevity of the design and material.

The lifecycle cost of a product greatly affects its environmental cost. Every material used in construction exacts a toll on the environment. I’ll not argue the relative merits of plastic over fiberglass, or cement over wood, or aluminum over steel. Figuring out the true costs of the energy used by each process, the damage to the earth, and the recyclability of each material is beyond the scope of this forum.

In general terms, products will have a lower impact on the environment if:

· They are aesthetically pleasing, but not trendy, so that you can enjoy them for a long period of time;

· They have a modular design, constructed with replaceable parts so that they can be easily repaired instead of discarded should they suffer a mishap;

· High-quality, long-lasting materials appropriate for the intended environmental conditions are used in construction;

· They are made from distinct materials that can each be easily separated and recycled;

· They use materials from renewable resources;

· The company you purchase them from invests more back into conservation than it takes from the environment.

Light weight: Most of the large surface area planters I found were made of cement, which may be too heavy for balconies, and even for roof loading, at the expense of soil depth required for the plants.

Stability in high winds: While the weight of cement has an advantage here, proper design can greatly increase stability. Many planters and pots are not appropriate for outdoor use because the bases are smaller than the top and the surface of the soil may be so high that they are top heavy. If they are blown over, many may break or worse. In many locations, wind can routinely be in excess of 20 mph and may well exceed 70 in gusts. You need to consider: If my planter is blown over will it blow off my roof or balcony?

The Issue of Form to Stability

Even light gusts tip pots

Solution:

All in all, finding lightweight, attractive, large volume planters with drainage control that provide a thermal break with an appropriate design aesthetic in a variety of sizes proved to be impossible, let alone planters that would also stand up to the test of time and the rigors of the property maintenance team.

Existing Solutions:

I started landscaping my building in 2004 with the SeaCrest series of large planters from Tournesol Siteworks (previously Planter Technology - shown above) as a good plastic planter solution. Every planter available at the time had some compromise, so despite the institutional look imparted by the roto-molded plastic construction, they answered most of the other challenges.

I ordered and installed more than a dozen of the 48” round and 72” rectangular planters for the rooftop, where we were able to engineer in the load capacity to hold their fully wetted weight of at least 2,300 lbs for the cylindrical planter and 1,500 lbs for the rectangular planter. We planted the round planters with 6’ high 3-stem Robellini palms. We planted two Jatropha bushes in the rectangular planters.

I highly recommend this company and their planters if the look of their products is appropriate for your venue. They make many of the liners we use in our planters, especially when we need custom sizes and forms to fit custom projects for customers.

While the SeaCrest planters are designed with self-watering reservoirs, we found that it was better to put them on drip irrigation (more about that later), but the double wall design for the reservoir planter provided just the thermal break that has allowed our plants to thrive despite the baking Miami sun.

The drainage is a bit iffy, but if you take the extra steps I outline below you should have good results. One other issue with the long 72” rectangular planter that arose is that the middle of the planter tends to bulge from the heat of the sun combined with the pressure from the soil, which creates a “creep” in the plastic. I understand that Planter Technology may have added a baffle in the middle to prevent this. I think that “creep” could be a problem for almost any single wall planter made from non rigid material like plastic, resin, and even fiberglass as the thickness required without a “web” for large plantersis cost prohibitive.

A New Concept:

Since I found that there were really no planters on the market for the balconies and rooftop deck on my project that fit the demanding criteria for large modular planters, I created DeepStream Designs to create commercial planters of a Landscape Architect grade that would meet the complex design criteria I listed above.

I’m not going to recreate the commercial DeepStream Designs.com website here, but since a picture is worth a thousand words so you may want to give www.deepstreamdesigns.com a quick lookover so that the information below has some context. You may notice that at this point I have only designed rectilinear forms.

Ultimately, to create planters with the large surface area and aesthetics that I was looking for, along with an unlimited variety of dimensions and materials, I had to create two different planter systems: The Mariner Planter for the special challenges of wood and the Audubon Planter that allows planters to be constructed using any other material suitable for outdoor use. Both designs rely on the science and engineering of DeepStream’s “Liner within a Planter” concept for the ultimate health of the plantings, while providing the lowest lifecycle cost for the planters.

Mariner planters were designed exclusively to overcome the challenges of constructing wood planters that will last decades while showcasing my favorite material. This is a frameless modular system that allows the wood to expand and contract within the slot of a heavyweight marine anodized aluminum leg without destroying the structural integrity of the planter box. Since the planking is free to expand, but held at the ends by the legs, the planks are essentially the frame.

Audubon Planters use DeepStream’s unique modular Anti-Gravity©frame system that allows planters, or façade systems of any size, to be made from panels of any suitable material.

3Form Bear Grass UV filtered resin

DeepStream’s unique frame system allows the use of any appropriate material

Slate

Slate

Any stone can be used, here is green marble. Raised feet allow for easy cleaning on balconies

Copper or any appropriate metal

Shared Design Features

In theory, only the length of available wood planks for Mariner planters and panel material for the Audubon planters would limit planter size; however, with intermediary legs, the size of either system can be expanded to infinity.

In practicality, the size of a single Mariner or Audubon planter box is limited to 72” in any one horizontal dimension. Dimensions over 72” require that a planter box become a facade that hides a planter liner, or a series of liners, which rest their weight on the building instead of being suspended by the planter box legs. Practical considerations include not only available wood plank lengths, or material sheet size and stiffness for the Audubon planter, but also available planter liner sizes and the combined weight of the soil and plantings.

Planter liners are constructed from High-Impact Polystyrene and Low Density Polyethylene (LDPE). The separate planter liner is a critical design component, providing a thermal break between the planter box, which absorbs solar gain, and the roots, thus ensuring that the soil is never warmer than the ambient air temperature. This design feature is crucial for plant health on rooftops and southern exposures and cannot be overemphasized.

The liner hangs from a frame attached to the legs,  This keeps the edge of the planter hidden, allows air to circulate, and no leaves or dirty water collects.  Drip irrigation lines can be attached to the frame keeping it out of sight and run up to the planter hidden between the liner and the exterior planter box.

The separate waterproof liner also is the key to preventing contact between wet soil, wood, and metal. This design feature ensures greater durability of all materials, thus providing the longest product life, the lowest possible lifecycle cost, and the lowest impact on the environment.

DeepStream’s two-part “Liner within a Planter” design is also a key component in drainage control while making watering easy, efficient, and attractive. Every liner can be fitted with an optional drainage system that uses a fitting placed through the liner wall about an inch-and-a-half above the bottom, a filter, a valve, and a hose that can be hooked up to a variety of drainage systems.

The drain, fitted to the wall of the planter liner, is more protected from blockage common for bottom-mounted drains. It also provides space for water to accumulate in dry periods to reduce water use and promote plant health. It is a water storage space that can be increased by closing the valve during dry seasons or periods of watering restrictions. The valve allows the drain to be opened during heavy rains to prevent dirty water overflowing from the top of the planter. During heavy rains, the rain will wash away filtered water even without a drainage system hooked into the building’s storm drain system.

Reservoir planters may be mandated by existing building design in some public areas due to complexities of providing a water source. However drip irrigation, with a timer and rain sensor, along with DeepStream’s drainage control system, which eliminates drowning the deeper-rooted plants, has proven to be the best way to water plants on our building.

Drip irrigation provides a natural top-down watering of the soil using a combination of drip emitters, spray heads, and misters that are best for simple and complex plantings with roots systems at different soil depths. Drip irrigation systems can be run off a low pressure “rain barrel” or the building’s high-pressure water system. Unlike single wall planters or pots, DeepStream’s two-part “Liner within a Planter” design hides drip irrigation lines that must run visibly up the outside of single wall planters or pots.

Materials:

Durability, modular design with replaceable parts, low lifecycle costs, and minimizing impact on the environment all go hand in hand. To ensure that planters are durable enough to last for decades DeepStream manufactures its wood planters using recyclable marine-grade anodized aluminum and stainless steel fasteners assembled with a special dielectric paste to prevent electrolysis between the dissimilar metals. Aluminum is the world most abundant mineral and it also uses the least amount of energy to be recycled.

The feet on DeepStream’s planters keep the wood from the wet deck, preventing rot induced by wood resting in standing water. They are made from HDPE, a recyclable marine plastic that will not scratch decks and will not absorb water. Our planter liners, constructed from High-Impact Polystyrene and Low Density Polyethylene, are recycled and recyclable.

Tropical hardwoods have been used for centuries in shipbuilding, dock, boardwalks, railroad ties and other extreme outdoor uses because their oil content makes them insect- and rot-resistant. Even so, these tropical hardwoods are not rot-proof and they can warp, twist, check and split, which to my mind adds character that is missing in today’s mass products. Our system will minimize all these aspects and contains the wood planks in a structural package for decades. If a plank should need replacing, the modular design means any plank or part of the planter can be replaced.

All of our wood is purchased here in the US so that it meets all environmental import source standards. Additionally, for every planter DeepStream sells, regardless of the construction materials, we plants 50 trees in Brazil. This is done in the name of the customer through a donation to Trees for the Future, www.plant-trees.com.

Almost any other materials can be used in the Audubon system and each has its own characteristics, longevity curves and environmental impact. For instance, there are fantastic looks in new UV-resistant resins from 3Form and Reynolds Polymer, just to name a few, that use natural material in the design and can be recycled. The primary laminate backing material for translucent resins is recycled and recyclable expanded PVC.

Tried and true marble or stone of any type, which can last for centuries, is given a new twist when we laminate it to ultra-stiff lightweight honeycomb aircraft aluminum panels so that a 42” planter box is lighter than wood, weighing in at about 52 pounds instead of hundreds of pounds. This allows marble planters, even with 18” of soil, to be used on a balcony or roof project. Even our largest 72” Mariner wood planter weighs only 112 pounds with a 16-pound liner. All of our planters can be shipped assembled and still go up an elevator or stairway easily, or they can be shipped flat and assembled in about 20 minutes if you have a Phillips head screwdriver.

Stability in high winds is a function of form, height and leverage. In high-wind situations, a square planter has better stability than a rectangular one, and a low planter has better stability than a high one. Of course, a low bush is going to impart less leverage than a tall thick clump of bamboo, while a high palm may allow the wind to just blow through.

Although we often get requests for planters with the top at about the 31”, our standard height is 21” plus a 1/2″ for the foot. This height allows for the standard height of the liner to accommodate 17” of soil, plenty for most plantings, while keeping the center of mass low. Aesthetically, it also allows the plant to be the focus of attention, instead of creating a wall of top-heavy looking planters. The lower height also keeps the cost down. If the intention in adding height is to screen a large space, our modular design includes a trellis accessory that combines rugged aluminum uprights and rustproof stainless steel mesh that will stand up to hurricane force winds, yet is not top-heavy.

Here in Florida, it is not possible to bring all the planters in off our large roof deck when a hurricane approaches. We have clips that can be mounted to the fasteners that hold the feet in the legs thus allowing the planter to be bolted to the deck. Many people, however, want to have the ability to move them about, or have rules or conditions that do not allow them to be bolted down so in extreme winds they may be blown over.

Because of these hurricane conditions, I have designed the planter liner to rest on aluminum straps suspended within the planter box. These not only ensure there is no funky accumulation of dirt or water to soil the deck under a planter, but if a planter should blow over and the planter liner blow out, the planter will not sail off the roof as it would if it had a solid bottom.

Additional Resources:

Books

Roof Gardens: History, Design, and Construction

Theodore Osmundson (FASLA)

W.W. Norton & Company, 1999.

A wonderful resource for large green roofs in general and waterproofing, with a table of information about weights of materials (p. 296).

Magazines

Fantastic sources of professional landscaping resources:

Landscape Architect and Specifier News (www.landscapeonline.com)

Landscape Architecture (magazine of the American Society of Landscape Architects – http://archives.asla.org/nonmembers/lam.html)

Garden Design (www.gardendesign.com)

Drainage

Variflow Technologies, Inc. (www.Varicore.com)

Multi-Flow professional drainage systems

Very good information on drainage and preventing blockage using coarse grain sand. Their products are great for large drainage areas.

High-quality large roto-molded planters

Tournesol Siteworks (www.tournesolsiteworks.com)

Drip Irrigation

Drip Works (www.dripworksusa.com)

While most plants do best with a consistent soil moisture content, many need to dry out between water applications.  Of course, some plants require special over or under watering applications.  A multi-valve multi-line drip system can use automatic timers to achieve both effortlessly.

To simplify your watering, it is best not to mix plants that may need different types of watering, fertilizing or soil in the same container. 

While this concept can also be extended to root depth, in larger planters it can actually work quite well as trees or bushes with deep roots can benefit from the needs of flowers with shallow roots that dry out more quickly to be watered several times a day with a  topical water spray which can augment a deeper root drip application line fed by a line on a different timer.

Generally, I run at least two 1/2″ main lines to feed perimeter planters:  one for the deep-rooted plants watered by drip irrigation soaker hoses with emitters on 6″ spacings, and another with sprayer and/or misters that either hang from taller trees or bushes or stand on spikes. 

In every case, I use in-line micro-valves on every 1/4″ feeder line from the 1/2″ main line to tailor the water delivery of each line to the planter, as the micro climates of each planter may vary considerably depending on exposure to sun and wind.

Delivering micro-doses of fertilizers on a consistent basis precludes the trough and peak delivery of single monthly doses of liquid fertilizers or the irregular dosing provided by slow-release coated dry fertilizers that depend on rainfall to dissolve.  Plants do better with this type of consistent feeding.

An advantage of installing different main line circuits for different types of plants is that a fertilizer injector system can be installed upstream of the valves.  Running one valve at a time, you can meet the needs of different plant types with different types and proportions of fertilizers with just the flip of a switch.  

 A visit to Dripworks’ catalog will give you a good overview of the types of products available that make this very easy.  Here is a picture of my manifold setup, which along with the drip irrigation on 4 circuits, was installed in a single  afternoon:

DeepStream Design’s modular planter design means that any aspect of the planter can be customized for any location.  Whether it is material or size, almost any special need can be accommodated.

Here are some pictures of planters, part of a larger project, where the Designer needed 12” subwoofers hidden in the planter.  Using a longer extrusion, for a higher leg, we were able to place the subwoofer under the planter liner.

Finished planter

speaker mounted under liner support straps

looking down into planter liner with drain that lines up with port through the speaker, drain hose and top caps to be mounted on site are inside, foot caps temporarily caping legs during final assembly

We started with the specifications from the speaker company regarding the optimum volume and material for the speaker box required for the best sound quality.  Using a special waterproof weather resistant material that met the speaker company’s resonance specifications, we built a waterproof speaker box that would retain the exact optimum interior volume after we added the necessary waterproof pass-through ports for drain and drip irrigation lines. 

The height of the planter box was a result of the critical foot print dimension specified by the Landscape Architect and Interior Designer.  Their design called for the planter to sit exactly on top of a specific paver size that would have a conduit for hidden power and speaker cables ported through a hole in its center.  With our custom capabilities we were able to give them the exact installation they needed for both the speaker and the liner, with the necessary drainage and root depth that the specified planting called for.

While we usually outsource custom planter liners, in this case we built liners in house. Using sophisticated composite technology from the yachting industry, we were able to ensure that there would be absolutely no give to the liners and that they would be waterproof for a century, even if a careless landscaper used a shovel to dig out the plants at some point in the future.

Some people argue global change is normal state, that there is no proof of human impact on climate change, it is just a normal process humans have no impact on.

Climate change may have normal cycles, but there is nothing historically normal about the human population explosion and the impact that their energy consumption and pollution has on the earth’s bio systems.  Many independent thinking people believe that the individual CAN make a difference.  However, working in conjunction with Architects we could do a lot more.

Not only do high concentrations of people in mega-buildings concentrate green house gas, but building these high-density buildings also increases the surface area on, if not of, the earth that can absorb heat.  It is not just office towers; residential condo towers are creating increasingly dense urban and coastal areas that contribute to the formation of “heat islands” and global warming by adding heat-retaining surface area.   Any city resident knows that it is often 10 degrees warmer in the city than the suburbs or rural areas around them.

The Green Roof movement is great, but the ratio of wall to roof area is much greater on high-rise buildings.  If Architects designed balconies with drainage and water spigots built into their clients’ high-rise buildings, it would allow residents and offices to help offset their impact to a far greater degree both in terms of cooling and exchanging oxygen for carbon and absorbing other pollutants.

Successful landscaping and gardening on balconies and rooftops, especially of condo towers, has many challenges that residents with terrestrial gardens in homes don’t share, especially if the building Architect is not on the same page.  Balcony and rooftop gardening, however, can help offset the green house gas emissions and despite the difficulties in cooling these heat islands, it is a worthy endeavor within the grasp of individuals using low tech, renewable resources.

“Gardens in the Sky,” by Don Sussman: 
http://grounds-mag.com/mag/grounds_maintenance_gardens_sky/index.html

Don Sussman the author and is President of Town and Gardens, Ltd., New York, NY http://www.townandgardens.com/greenroofs.html

“From the Top,” by Tracy Powell:
http://grounds-mag.com/mag/grounds_maintenance_top/index.html