Inside Urban Green

LED Lighting Leads the Way at the Pentagon

Fluorescent lighting

LED lighting

The Pentagon has initiated a project to install LED lighting as part of a 10-year renovation. Over 4200 Cree LR24 recessed LED luminaires will be installed in Wedge 5 of the 5-sided building.  

Government studies conclude that the LED lighting installation will have a payback of <4 years and is estimated to save 140 tons of carbon dioxide emissions per year.

It appears to be only a matter of time before we have widespread availability of LED lighting at an affordable price. This has the potential of increasing the use of plants in buildings, both commercial and residential. 

Via: LEDs Magazine 

Step by Step to Healthy Plants in Containers

The following plant care guide is a work in progress. The emphasis is on indoor or houseplants but the basic principles apply to both indoor and outdoor plants growing in containers. I plan to add videos in the near future.

In an effort to improve the clarity of this guide, it will be most helpful if you would make constructive suggestions or ask questions either by comment or email me at urbangreenscaper [AT] gmail.com. Thank you on behalf of other readers.

The first three rules of container plant care…measure, measure, and measure

It’s easy to understand why so many houseplants look unhealthy and why so many people feel they have a black thumb.

The undeservedly popular drench and drain method of watering is tricky to learn because it’s all art rather than science. It’s based on feel and estimating rather than measurement. It might be okay for the greenhouse but not in your house where light is scarce and the environment sometimes harsh. 

Poking your forefinger in the soil to feel the soil moisture and using window direction to estimate the light level is hardly scientific and highly subject to error.

For most of us, human judgment about measuring light and soil moisture is woefully inaccurate. Human judgment may work for plants in the sun when photosynthesis is at its peak but not in low light building interiors. The margin for error is quite small.

What follows applies to any plant species whether grown for foliage or flowering decoration or for food production. The only difference in these categories is the level of light required, vegetables being at the top of the chart. Sub-tropical foliage plants require the least amount of light but even they will die without adequate light.

The key to success is to follow the golden rule of light-water relationships

Floor Lamps for Floor Plants

Pablo Cortina lamp from DesignPublic.com

It is unlikely that these lamps would supply enough light for large floor plants but they look like they could. A long time ago, I made a floor lamp from a sonotube standing on end with a 4' fluorescent shop light inside. I cut an opening for the light and muted it with a piece of plastic diffuser. All of this was purchased from Home Depot and it was relatively easy to make. 

The important point is that it works. You can supply enough light to support healthy growth of a Ficus benjamina tree with a vertical lamp like this. It is, in fact, better than overhead light. The light is distributed to the full length of the foliage, not just the top. 

 

Rotate the tree periodically to even out the new growth and maintain its symmetry. Think of the lamp as an artificial window.  Connect it to a timer so that the lamp comes on when the room is unoccupied if you prefer. The plant won't care. 

It would be relatively easy for a lighting manufacturer to produce fluorescent floor lamps like these. Once again, it's a problem of education. Overhead fluorescent plant lighting is very common but using it vertically is out of the box thinking. 

I'm going to contact a lighting manufacturer here in Brooklyn and see if they would build some prototype models for beta testing. Would you be interested in something like this? 

Compact Fluorescent Color Confusion

 

There are two significant considerations when buying compact fluorescent bulbs for maintaining desktop or tabletop houseplants. They are wattage and color rendition.

Of the two, wattage is more familiar from incandescent lighting days. I would recommend 23 watt CFLs that are equivalent to 150 watt incandescent bulbs. This is a little less than what this 27-watt lamp puts out. 

Color is another matter and can be confusing. My preference is what is referred to as "daylight". To my eyes, it is the most natural light to display plants. You may prefer "bright white" or "soft white" which is similar to incandescent light. 

Apparently the bulb package color is supposed to guide consumers. Blue signifies "daylight", red is "bright white" and green is "soft white". 

I was fooled by this color coding and bought a Sylvania SuperSaver 23 watt CFL in a box with blue printing. It is a "bright white" CFL, not a "daylight" bulb. Caveat emptor! 

In some stores, Home Depot for example, you can see the difference in an in-store demo. This is a good idea!  

More Low Cost Desk Lamps for Plants

This lamp was a Wal-Mart purchase for about $10 a couple of years ago. I don't have a Wal-Mart handy so I don't know if they're still available. If they are, they likely cost more now. You can compare it to this one. 

Note that a 23-watt (150 watt incandescent) bulb does not fit the shade of this lamp. I made an extension from a plastic food container (the sprayed black rim in the photo above) that fit inside the shade. Otherwise, the bulb sticks out beyond the shade, which may or may not bother you.  

This clamp on lamp that looks similar. It’s from Wal-Mart online and costs $18.88 plus shipping. This shade also looks too shallow to conceal a 27-watt CFL. It surprises me that the Chinese manufacturer hasn't modified these shades by now to fit CFL bulbs. 

If you find the retail lighting market to be confusing, you're not alone. I'm going to attempt clarifying CFL lighting information as it relates to plant lighting in a separate post. Stay tuned.  

Light a Plant Compact Fluorescent

 

This affordable desk lamp from Lights of America is an effective way to maintain a tabletop or desktop plant within your view at home or work. The lamp uses a 27 watt (150 watt incandescent equivalent) compact fluorescent rated at 10,000 hours. 

Plug it into a timer for automatic lighting control. A 12 hour day would be adequate for most low light tolerant houseplants. Increase the time to 16 hours for high light requirement cactus and succulents as pictured. 

These plants are watered by sub-irrigation and are growing in a microwave food cover with an 'aquapad' under it. Sub-irrigation provides a consistent level of soil moisture which reduces stress on the plant. This is of significant help in improving an indoor plant's tolerance to lower light. 

Home Depot is one source at a price of $22.00. There are others online. 

Approximate light levels

Distance from lamp Approx Foot candles 

 3" 850 f.c. 

 6" 330 f.c 

 9" 200 f.c

12" 130 f.c. 

Sun Tunnel Skylights

Sub-irrigation solves container plant watering problems but available light is still the limiting factor. 

Supplementary artificial lighting using fluorescent tube fixtures and CFL lamps is one solution. For a natural light solution, have a look at Velux D.I.Y. sun-tunnel skylights. The photo above is of a commercial sun tunnel skylight application. 

Hopefully this type of lighting solution will be incorporated more frequently in new and renovated building projects. It's seems to be a good green solution to providing more green in building interiors whether home or office.  

Via: Re-Nest  an Apartment Therapy blog

Plants to Light Plants

An Inhabitat post about this solar cell module in plant form reminded me that I had seen it earlier this year on the Japanese website Tach-on!.  

On seeing this, my thought was that perhaps one day in the future solar power could be used to maintain indoor houseplants. Aside from our reactionary horticultural education system, light is the limiting factor for the use of plants in buildings.  

What if we could position a small solar collector like this in a sunlit location? It could then power lights for our indoor plants. Solar power and highly efficient LED lighting could one day propel a great leap forward in the use of urban greenscaping and urban agriculture. 

Let's all hope that we find the forward looking leadership to make it happen.  

L.E.D. There be Light

J.R. Krauza

Will the green home of the future have L.E.D lighting sufficient to maintain decorative plants or even better to grow edible plants?

This article from The New York Times is encouraging. Incidentally I read this article in context of how misinformed the Times reporters can be regarding the maintenance and growing of container plants. That is a subject that I'm qualified to critique professionally.

However, I simply don't know enough about L.E.D. lighting technology to analyze this article in detail. If you do, please comment for the benefit of other readers. Here are some reader reviews of the article.

There is obviously significant money betting on an L.E.D. future. Will the living plants sector of the “green” movement be a significant player? Only time will tell, but the past is not a good precursor of the future.

Hopefully, projects like the “Smart Home” in Chicago, will soon demonstrate the use of L.E.D. plant lighting along with sub-irrigated planters. It will certainly make these homes a lot greener.