Rooftop Greenhouse


Located at the very top of the shiny new Exploratory Hall building is the ESP Greenhouse, which is managed by Monica Marcelli and her crew of dedicated assistant managers and student volunteers.

Entry to the 54′ x 31′ greenhouse is controlled by secure elevator keycard. Upon entry, one sees the prep room, which is a fully-equipped work area where plants are pruned and prepared for their new home. The greenhouse is divided into two main rooms, one with low humidity and the other with higher humidity. The plants are then separated and placed in the room which suits each type of plant best.


The President with ESP staff. From left: Aikwan Chong, Monica Marcelli, Ángel Cabrera, Sharon Bloomquist.


Automated shades, roof vents, and fans.

One impressive feature of the greenhouse is that it has a fully automated climate control system. The temperature and humidity in each room can be programmed individually. In order to maintain the desired temperature and humidity levels, the roof and side vents will open or close, and a fine spray mist and fans will turn on and off on demand. In addition, the shades at the top of the ceiling can also be adjusted to open and close according to light intensity. The new greenhouse also uses an automated drip irrigation system that can be programmed to irrigate in specific time intervals during the day, as well as the number of days per week. Each room has six stations that can be programmed independently.

Sticky trap

Sticky trap

The yellow sticky traps are one of the pest control methods used in the greenhouse.  Yellow attracts most insects, and blue sticky traps are also used to trap thrips.  Sticky traps provide useful information on the type of insect pests and the degree of infestation, and the effectiveness of overall pest control methods.

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Left: Epiphyllum oxypetalum (Dutchman’s pipe, queen of the night, orchid cactus) is a species of forest cactus native to central and northern South America. This intriguing cactus blooms only once late into the night and the flower lasts only the one night.
Right: Bryophyllum daigremontianum (Mother of thousands, alligator plant, Mexican hat plant) is native to Madagascar. The margins of its leaf-like organs have plantlets that form roots while on the plant. Each plantlet can sprout a new plant when it falls onto soil. All parts of this plant is toxic to humans and animals.

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Above: Green fern with sori on the underside of the leaves. Sori are clusters of spores, by which ferns reproduce.
Below: Tradescantia zebrina, formerly known as Zebrina pendula (inch plant, wandering jew) is native to the Gulf Coast region of eastern Mexico. 

Cycas revoluta (king sago palm, sago cycad, Japanese sago palm) is native to southern Japan. In spite of its common names, this plant is not a palm, but a cycad (prehistoric plants that have been around during the Permian era over 200 million years ago and predates the dinosaurs.


To schedule a visit to the ESP Greenhouse, contact Monica Marcelli by email or call 703-993-4043.

Important Dates for Students

SPRING 2020 Semester (modified due to COVID-19)

MLK Day (university closed): Jan 20

First day of classes: Jan 21

Spring Break (extended): Mar 9-20

Dissertation/Thesis Deadline: May 8

Last day of classes: May 11

Reading Day(s): May 12

Final Exam Period: May 13-20

University Commencement: May 22 (tentative)

COVID-19 DATE CHANGES – For the complete modified spring calendar, see and for latest COVID-19 updates, see: