Thursday, August 30, 2007

3-Week Course Evaluation

We want HCC's distance learning courses to be the best they can be. Your early feedback will help us reach that goal. Please take a few minutes to complete a brief evaluation of this course. You will have until 11 p.m. Friday, September 7 to complete the evaluation.

To evaluate this course, click here and enter the following 3-digit PIN where prompted: 778

Please note that all evaluations are processed by the College's Office of Research and Institutional Effectiveness. Your responses and comments are anonymous and your instructor will only receive summarized results at the end of the evaluation period. We appreciate you taking a few minutes to provide a frank and honest evaluation of your course.

Jonathan Vester, Coordinator of Research and Institutional Effectiveness

Wednesday, August 29, 2007

Module 3 - Greenhouse Heating - DUE Tuesday, September 11th


Effective and economical greenhouse heating is the union of an appropriate heat source and an efficient heat distribution system. The best greenhouse heat source in the world is useless if the heat cannot be transferred to the plant environment. Likewise, an efficient heat distribution system is useless if an adequate heat source is not used. The most efficient greenhouse heat source and the most efficient heat distribution system can continue to work well -- only when properly maintained.


* Evaluate the strengths and weaknesses of different types of heating systems
* Calculate the heating requirements for a greenhouse.
* Operate greenhouse heating systems in a safe manner.
* List standard maintenance requirements of greenhouse heating systems.


greenhouse effect
solar heat
radiant energy
LP gas
solar energy
perforated polyethylene tubing
natural gas
horizontal unit heater
central heat
a^2 + b^2 = c^2
aspirated thermostat
area of a right triangle = 1/2bh
finned pipe
zoned heating
unit steam heater
carbon monoxide
heat exchanger
sulfur dioxide


NGMA Heating Tips (75.094 Kb)

1. Read pages 93-159 of the textbook.

2. Read NGMA helpful heating tips (link above3).


1. Watch heating slide show embedded in blog post.

2. Watch the Crossroads Farm (VT) 'Heater Problem' video. Describe what happened to Tim and Janet Taylor when they expanded their greenhouse. (5 pts)

3. Submit use the internet to determine what the record low is for each month where you live (you may need to use a town near you if you live in a rural area). HINT: The Weather Channel has such records available for public viewing. (5 pts)

4. Use the Virtual greenhouse to run the following three simulations (don't adjust any additional settings that will come later):

* Burlington, VT; Winter; double poly, quonset style house, no heater, with set points.
* Burlington, VT; Winter; double poly, quonset style house, 1 heater, with set points.
* Burlington, VT; Winter; double poly, quonset style house, 2 heater, with set points.

Describe what happens in each setting. Make sure you pay close attention to the y-axis on the Air temperature graph. (10 pts)


1. Compare and contrast unit heaters and boilers. Explain the advantages and disadvantages and what types of operations might use both. (10 pts.)

2. Unit heaters are very common with growers who have relatively small amounts of production space. However safety is always an issue. (10 pts)

a. describe the appropriate positioning of the exhaust pipe.
b. why does a grower have to insure a constant source of fresh air when the heater is running.
c. what are two potential byproducts of a poorly functioning heater that are damaging to plants
d. what is a byproduct that can be extremely dangerous to humans
e. What must you do first if you get an alarm in the winter that a heater is off in your ornamental greenhouse?

3. Explain the advantages of an infrared heating system. (5 pts).

4. You have a single a-frame greenhouse with the following dimensions. (You may want to start by drawing yourself a picture). The dimensions are 50 ft (length) X 24 ft (width) X 8 ft (eave height). The ridge is 19 ft high. The glazing material is twin-wall polycarbonate. You want to be able to hold an inside temperature of 55 F even when the temperature outside is 0 F and winds are 20 mph There is no curtain wall. (25 pts)

a. calculate the heat loss/hr (show all your work. HINT: you may want to work through the problem on pages 137-139 STEP-by-STEP. USE THE SAME STEPS FOR THIS PROBLEM. (call me if you have difficulty we will work through it together). If you have difficulty showing the math on Google Documents you can mail me hand written sheets, just make sure they are postmarked by the module due dates.

b. search the internet and locate a unit heater(s) that will supply the amount of heat you calculated. Explain your choice. Don't worry about brand names and cost just BTU output. Please put the website in your answer so that I can check it.

5. You have a gutter connected a-frame (each bay roof) greenhouse with 3 bays and the following dimensions. (You may want to start by drawing yourself a picture). The dimensions are 100 ft (length) X 72 ft (width, each bay is 24 ft in width) X 20 ft (eave height). The ridge at the center of each bay is 26 ft high. You want to be able to hold an inside temperature of 55 F even when the temperature outside is -10 F. The material covering this metal greenhouse is single pane glass. Your greenhouse happens to be located in a very windy area. So count on 35 mph winds on this -10 F winter night you are planning for. (30 pts).

a. calculate the heat loss/hr (show your work)

b. you have decided to have a boiler installed and you will use 2" iron plain pipe (no fins) to deliver the heat to your greenhouse. How many feet of pipe will you need to deliver the amount of heat required on the cold night that you designed the heating system for? How many feet will you need of finned pipe? (see page 79 in your text for a hint).


I was fascinated by this greenhouse gallery. The ingenuity these people displayed in creating their own local controlled environments was awesome. Most folks were novices. Imagine what you will be able to accomplish once you have successfully completed the course. Imagination + Knowledge = Success

Friday, August 17, 2007

Turning in Assignments

Make sure you have turned in your HOP Assignment. All students must turn in the HOP Assignment by August 24th or they will be dropped from the course.

If you have turned in your HOP Assignment you be wondering how you will turn in other assignments. Below is a video to help get you started. I know it is a bit fuzzy, but watch the mouse pointer and try to create a document on your own e-mail account. Please contact me if you have any questions. I would be happy to help out. MODULE 1 is due August 28th by midnight.

Friday, August 10, 2007


Lettuce seedlings at Epcot. Image Source: sylvar

Welcome to Fall Semester 2007 at Haywood Community College. You are enrolled in the online section of HOR 134 Greenhouse Operations. I hope you find this material as exciting as I do. Understanding the fundamental principles of greenhouse operations will help you produce floriculture crops more efficiently and economically.

Please take time to familiarize yourself with the Blogger Environment. If you are new to Blogger an easy way to start is by following all the links in the Course Menu at the right. Also be sure to read the announcement concerning the HOP Assignment. The HOP Assignment must be completed by August 24th or you will be dropped from the course. This is a simple assignment that serves as a record of you having signed onto the course.

Please also read the syllabus thoroughly. If you have any questions please contact me. I would be happy to answer them. My physical office is at Haywood Community College in 1105 at the Nix Horticulture Complex. My office phone is 828-565-4275. The e-mail I want you to use to contact me is .

Make sure you sign up for a free gmail account at I will be using this e-mail to contact you and we will be using other google applications during the semester.

Thank you for your interest in horticulture technology and I look forward to a successful course this semester. I am always happy to assist students, so if you have any questions, concerns or constructive criticism please contact me.

Thursday, August 9, 2007


In order to remain enrolled in your online classes, you must complete the Haywood Online Prep (HOP) assignment for each course you are registered to take. Students who have not "hopped" by 4:00 p.m. Friday, August 24, 2007 will be marked as a "no show" and dropped from the course.

  1. Go to and sign up for a free google account. This will be the e-mail you use exclusively for this course.

  2. Place your cursor over this link and click your right mouse button. A pop-up menu will appear.

  3. Choose the Save Target As option (Save Link As in Firefox).

  4. In the Save in box, select the location where you wish to save the document on your computer.

  5. In the File name box, change the file name to your full name.

  6. In the Save as type box, verify that the file type is Rich Text Format.

  7. Open the HOP Assignment file on your computer using your word processing program.

  8. Type your answers to the eight (8) questions in the file. Be sure to Save the changes.

  9. After you complete the work, log into your Gmail account and send an e-mail to me ( with the RTF file you created as an attachment.

When your instructor acknowledges receipt of your file, a check mark will appear next to your name in the online gradebook.

* A file saved in Rich Text Format (RTF) is a text file that contains formatting instructions that most word processing software applications can understand. Saving files in this format ensures that your instructor can open your assignments even if he or she uses a different word processing program. For help saving files in Rich Text Format, click here.

Image Source: SC Fiasco

Module 2 - Greenhouse Construction - DUE SEPTEMBER 4th.

In many cases students will be planning to construct new greenhouses or purchases existing greenhouses when considering a new horticulture business venture. One often overlooked process is the planning involved with site selection.

There are many decisions to made in a business plan prior to the construction or purchase of a greenhouse. These are critical to economic success. I have met more than one gifted enthusiastic horticulturalist that met economic hardship by diving headlong into production without first spending the necessary time to come up with a thoughtful business plan.

New greenhouse construction in Chicago, IL. Image Source: clare and ben

Choosing the type of greenhouse you need for production is a complicated process. Sometimes a simple structure will suffice and may result in positive economic returns. Other times labor costs combined with a target wholesale market may be decision drivers in choosing a more complex structure such as that shown in the image above. This house below is a high profile gutter-connected range. Sometimes rolling benches are added to further maximize the utilization of light for crop production.

Large glass greenhouse range in Holland. Image Source: akbar1947.

  • Understand the importance of a business plan prior to making any decisions involving greenhouse operations or management.
  • List what decisions have to be made before the greenhouse business plan can begin.
  • List and explain a dozen factors that are integral to greenhouse site selection.
  • Be able to recognize and name different types of greenhouse structures.
  • Identify the various components of a greenhouse.
  • Discuss the advantages and disadvantages of different types of glzing materials.
  • Discuss economic factors to consider when constructing a greenhouse.

growing period
growing media
annual production
marketing system
investement capital
property value
labor law
H2A Visa
building code
low tunnel
high tunnel
water quality
gutter connected
high profile
snow fence
low profile
safety glass
plastic resins
gutter connected
bench washing machines
even span
uneven span
float glass
tempered glass
ebb and flow
bar cap
rolling benches
galvanized metal
expanded metal

  1. Read summary of Greenhouse Construction from WSU as a primer.
  2. Read Chapter 2 in your textbook. pgs. 41-90
  1. Watch the Site Selection microlecture. This mini-presentation is about 22 minutes, so depending on your Internet Connection Speed it could take anywhere from 5 to 50 minutes to download. I would start the download process and then read your texbook while you wait.

  2. Watch the Greenhouse Construction microlecture. This presentation will walk you through the basics of greenhouse construction to supplement your textbook reading.

  3. Watch the Greenhouse Glazing microlecture. This presentation will help you review the material covered in the text.

  4. Watch the Greenhouse Benching microlecture. This lecture covers the variety of benching material that you may find in the world of greenhouse operations.

  5. Watch the structure videos from each of the greenhouse locations we will be highlighting this semester. (at the bottom of this section)

  6. Watch the video from Kraft Gardens in Florida entitled "Building for Hurricanes." (Below)

  7. Review greenhouse construction by viewing the following slides.

  8. Last week you were asked to visit a greenhouse and take some pictures (if you have access to a camera...don't worry about images if you don't have a camera). Please post the name and location of the greenhouse you visited to the discussion board. In additional include the following on the discussion board: Briefly describe the business (i.e. wholesale, retail, bedding plants, mass market, specialty, etc.) Briefly describe some of the site characteristics. What do you think worked about the layout of the greenhouse or greenhouse range? Was there anything you might change? (10 pts)


I. Organic University: Greenhouses for year-round food and farming Part 1: Greenhouse site selection Before you get there, you need to know just where you?re growing. By Katie Olender

A good review of some major site selection factors for those interested in organic food production in greenhouses.

II. Selecting and Building a Commercial Greenhouse

By John W. Bartok, Jr., Agricultural Engineer at the U. Mass Amherst.

A great review of all major site selection factors. This is the reference that much of the microlecture is based on.

III. Sample Manufacturer Brochure on Greenhouse Design and Overcoming Site Selection Difficulties.


STUDY QUESTIONS (Answer in Complete Sentences)
  1. for the purposes of this question imagine that you are going to start a new greenhouse business at your current place of residence. In this imaginary scenario the area of land you have is not limiting nor is capital for investment. (10 pts)
    • Discuss the Environmental, Land, and Resource Considerations for your site.
    • Do you think your site would be more suitable for a retail or wholesale business? Explain why.
    • What do you think the most limiting factor would be at your site? There is no right or wrong here, but explain the reasoning that lead you to your answer.

  2. Which side of a greenhouse should the headhouse be located on? Why? (10 pts)

  3. How is producing plants different from a manufacturing business such as making furniture? What are some similarities? (5 pts)

  4. List three federal government offices that have free information available that would assist in site selection for a new greenhouse. (5 pts)

  5. Compare and contrast 3 different types of greenhouse glazing materials that are commonly found commercially. Be sure to thoroughly cover the strengths and weaknesses of each. (10 pts)

  6. Describe the strengths and weaknesses of wood framed greenhouses as compared to metal framed greenhouses. (5 pts)

  7. What are the advantages of a high profile greenhouse? low profile greenhouse? sawtooth style house? (5 pts)

  8. What is the primary advantage of a gutter connected greenhouse? (5 pts)

  9. Describe 3 different types of benching. (5 pts)

  10. Describe important considerations for greenhouse directional orientation. (10 pts).

  11. What are some of the special features of the Florida greenhouse in the video that allow it better withstand damage from hurricanes? (10 pts)

  12. In what situations do you think a glass covered greenhouse would be appropriate? Are there situations where double poly might be preferred? (10 pts)

Wednesday, August 8, 2007

Module 1 - Greenhouse Industry Introduction - DUE AUGUST 29th

Over the past decade, floriculture and nursery crops have been one of the fastest growing U.S. agricultural sectors. Of the estimated $45 billion in U.S. horticulture sales in 2003, floral and nursery crops contributed a third, or $15 billion, less than vegetables' sales receipts of $17 billion, but more than fruits and nuts' $13 billion. ERS analyzes conditions and trends that influence supply, demand, trade, and prices in the domestic floriculture and nursery markets. -ERS 2006

It is important to remember that overall trends are based on regional components. A bright outlook for the industry as a whole may not translate to every greenhouse production area in the United States.


  • List and Describe the areas of major greenhouse flower and food crop production in the United States.
  • List the ten highest value florist crops.
  • List the top 5 states in floriculture production.
  • Explain why tomato producers located in Mexico may be increasingly competitive with greenhouse tomato producers in the United States.
  • List 8 sources of recent greenhouse horticulture information.
Floriculture Agricultural Research Service National Agricultural Statistics Service
green plants American Society for Horticultural Science
flowering pot plants FloraCulture International
bedding plants International Association of Horticultural Producers
foliage plants Greenhouse Business Magazine
cut flowers Greenhouse Grower Magazine
annuals The Green Beam
perennials Greenhouse Product News
USDA/ ERS Grower Talks Magazine

Green Profit Blog

2006 Floriculture and Nursery Crops Yearbook (661.938 Kb)
  1. Read pages 1-10 of the Floriculture and Nursery Crops YEARBOOK published by the ERS/USDA.
  2. Familiarize yourself with the latest published Statistics on the Industry in the United States.
  3. Read Chapter 1 in your textbook. Floriculture a Global Industry. pages. 1-38. (We won't spend a lot of time on this, but this is useful information to know).

Watch the following videos.

Visit a local greenhouse and be prepared to answer some questions concerning your visit. If you have a digital camera take some pictures of your visit (always ask the manager/owner for permission prior to taking any photos).

STUDY QUESTIONS (Answer in complete sentences)
  1. What are the top five floriculture crops produced in the United States? (10 pts)

  2. What are the top five floriculture production states? (10 pts)

  3. What are some of the advantages that growers have in California and Florida that make their greenhouse industries so large? Despite these advantages why are so many companies moving some of their operations off-shore (for example Ecke). (10 pts)

  4. Theoretically, why would the USDA be a better source of factual information than a trade journal? Why would I use the word theoretically in the previous question? (10 pts)

  5. Differentiate between the greenhouse industry in Florida and California as introduced in the videos (20 pts) You will have to search the web for information regarding the California industry. The USDA ERS is a good place to start.

  6. Differentiate between the greenhouse industry in Ohio and Vermont as covered in the videos (20 pts)

  7. Why is it important to get the most recent news and be involved in the professional organizations of your chosen field of study? (10 pts)

  8. Describe one greenhouse related horticulture career that you find interesting (10 pts).
List of links on Horticulture Careers


Watch this videos to get a better feel for the types of work that greenhouse and nursery managers conduct on a daily basis.