The Roper Solar Greenhouse
215 Maywood Street, Blacksburg, Virginia
Located in the Hale-YMCA Community Gardens

Back to the main YMCA Solar Greenhouse web page

Regular Procedures

There are regular procedures that need to be done to keep the YMCA Solar Greenhouse in good operating condition.

Carbon Dioxide Level

There is a CO2 meter on the back of the center pole of the YSGH. The outside CO2 concentration is about 387 ppmv (parts per million volume). A tight solar greenhouse can cause the carbon-dioxide (CO2) level to become low, resulting in slow growth of plants. ("...plants will stop growing when the CO2 level decreases below 150 ppm. Even at 220 ppm, a slow-down in plant growth is significantly noticeable.") The door should be left open as much as possible when the weather is not cold to let fresh air with higher CO2 in; I suggest leaving it open when the Sun is shining and someone is working in the greenhouse. (Some commercial greenhouses use CO2 generators to increase the CO2 to 1000 ppmv or higher. "...increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels")

There needs to be turbulence to move fresh air with CO2 to the leaves. The YSGH has two features which create such turbulence: