1. Greenhouse Production and Maintenance
HORT II
February 28, 2006

2. Today: ~Review yesterday’s material and vocats questions ~New material on greenhouse maintenance ~Review new material

3. Review What is the main function of a greenhouse?
To beautify where it is located
To produce corn, soybeans, and wheat
To provide a protective environment to grow plants
To supply carbon dioxide and nitrogen for plant growth.

4. What is the main function of a greenhouse?
To beautify where it is located
B. To produce corn, soybeans, and wheat
C. To provide a protective environment to grow plants
D. To supply carbon dioxide and nitrogen for plant growth.

5. What environmental control should Joe use to cause lights to automatically turn on and off at certain times?
Carbon dioxide meter
Sterilizer
Thermostat
D. Timer

6. What environmental control should Joe use to cause lights to automatically turn on and off at certain times?
Carbon dioxide meter
Sterilizer
Thermostat
D. Timer

7. Lisa needs to install an environmental control to measure the light intensity in her greenhouse. When control device does she need to install?
Carbon dioxide meter
Exhaust fan
Photocell
Thermostat

8. Lisa needs to install an environmental control to measure the light intensity in her greenhouse. When control device doe she need to install?
Carbon dioxide meter
Exhaust fan
Photocell
Thermostat

9. Heat from the sun that greenhouses collect and store inside is:
Fossil energy
Kinetic energy
Nuclear energy
Radiant energy

10. Heat from the sun that greenhouses collect and store inside is:
Fossil energy
Kinetic energy
Nuclear energy
Radiant energy

11. Greenhouse effect is the way a greenhouse:
Collects and stores heat from gas heaters.
Collects and stores heat from the sun.
Protects plants from frost and wind.
Protects plants from insects and diseases.

12. Greenhouse effect is the way a greenhouse:
Collects and stores heat from gas heaters.
Collects and stores heat from the sun.
Protects plants from frost and wind.
Protects plants from insects and diseases.

13. A medium sized evergreen shrub with 1” long and ½” wide dark green leaves and ¼” diameter black berries is:
Evergreen Candytuft
Hetzi Holly
Parlor Palm
Sycamore

14. A medium sized evergreen shrub with 1” long and ½” wide dark green leaves and ¼” diameter black berries is:
Evergreen Candytuft
Hetzi Holly
Parlor Palm
Sycamore

15. 7. What is this plant???
Evergreen shrub that blooms October-December in the South

16. 8. Identify this plant…
Medium evergreen shrub with dark green 3” long and 1.5” wide leaves. Also 3” white very fragrant blooms.

17. New Materials From 7.02
Using and environmental controls for heat, air, light, and moisture.

18. One of the most important elements in greenhouse production is the thermostat. The thermostat is what controls the temperature inside the greenhouse. The thermostat should be placed at plant level inside the greenhouse.
This particular one is $71.00

19. Thermostats can be found from very simple to completely computerized
The Growmate Plus provides the luxury of computer-accurate environmental control to all growers. Five cooling stages, an air circulation stage, and two heating stages are featured.

20. Temperature Sensors - An aspirated thermistor senses the greenhouse air temperature near the plants to provide input for control of heating and cooling.

21. The thermostat also acts to control the sensors that open the air vents and operate the exhaust fans. The thermostat controls the sensors to pull air through fan and pad cooling systems.

22. The exhaust fans of the ventilation system can be seen in this picture.

23. NO COOLING 1. Inside temperature of greenhouse can exceed 140 degrees F.
2. Plants will die within a short period of time.

24. Why Do We Need Ventilation???
If hot air is not moved out the plants will begin to wilt and will die in a short period of time.
Also plants require carbon dioxide to survive. If the air is stagnant (lacking fresh air) the plants will suffer and possible die as a result.

25. There are several different methods of venting a greenhouse.
Natural
Fan and Shutter
Fan and Shutter with Shade Cloth
Fan and Shutter with Cooling Pad

26. NATURAL VENTILATION
1. Roof vent opens to allow hot air to escape to outside.
2. Door or other opening must be left open to provide for incoming air from outside to replace exhausted air.
3. On hot summer days temperatures can rise 20 to 30 degrees above outside temperature.
4. Recommended for mild climate areas only.

27. FAN & SHUTTER COOLING
Outdoor air is introduced through motorized inlet shutters.
Hot air is exhausted by exhaust fans.
Temperature inside house can be maintained within 10 degrees of outdoor temperature with properly designed system.
Fans and shutters are controlled by thermostat.

28. FAN & SHUTTER COOLING WITH COOLING PAD
Outdoor air is introduced through motorized inlet shutters.
Hot air is exhausted by exhaust fans.
Shade cloth is placed over exterior of greenhouse or suspended from wires placed on inside.
Temperature inside house can be maintained within 3 to 4 degrees of outdoor temperature with properly designed system.
Fans and shutters are controlled by thermostat.

29. FAN & SHUTTER COOLING WITH SHADE CLOTH
Outdoor air is introduced through motorized inlet shutters.
Hot air is exhausted by exhaust fans.
Shade cloth is placed over exterior of greenhouse or suspended from wires placed on inside.
Temperature inside house can be maintained within 3 to 4 degrees of outdoor temperature with properly designed system.
Fans and shutters are controlled by thermostat.

30. Dayton Shutter Fans
Easy-to install, efficient exhaust fans have automatic shutters. Heavy-duty guards have gray polyester coating to resist corrosion.   The 7” to 24” diameter fans have aluminum propellers; 30” and 36” fans have galvanized steel propellers.

32. Photocell
Photocells are devices that measures light intensity and send signals to computer that turns on lights or activates the shade cloth to control light.

33. Moisture in Greenhouse Production
A humidistat is used to control fogging or misting systems to regulate relative humidity or moisture in the air.

34. Heat = Loss of Moisture
Heat dries moisture from the air and moisture must be added by both watering and through misting or fogging for most plants.

35. Misting Sprays are a popular and effective way of watering delicate plants or those which thrive on humidity or dampness. Orchids, bromeliads or other tropical plants love a gentle settling mist.

36. Misting type sprays are frequently used in greenhouses, hot houses and shadehouses, or in sheltered areas of a garden : - near a wall or fence or under a pergola. They are easily installed overhead using flexible Polytubing. From above, the mist can drift into areas not easily reached by direct spray. Ferns respond particularly well to this environment which imitates their natural habitats : on the forest floor, in secluded gullies or near streams and waterfalls. In high temperatures, misting sprays will readily be absorbed into the air, increasing humidity which promotes the fast growth associated with rain forests.

37. Automatic Watering Systems
Digital and computerized watering systems are used to control the amount of water as well as to automatically disperse the water.

38. Other Watering Options: Netafim DripMat is a three-layer mat with built-in dripper line down both sides. The dripper lines distribute water evenly down the length of the mat and the central layer moves water across the width of the mat. After each irrigation, the mat drains for true ebb and flow watering

41. • Extremely even water levels result in uniform crops.
TrueLeaf Flood Floors:
• A wide range of crops respond favorably to sub-irrigation.
• Extremely even water levels result in uniform crops.
• Zero runoff eliminates pollution.
• No wasted water or fertilizer.
• Dry foliage reduces diseases.
• Short watering periods prevent transfer of fungus spores.
• Open growing space permits excellent flexibility and fast movement of crops.
• Simple design: reliability and low maintenance.
• Good sanitation is easy to maintain.
• Labor for watering is practically eliminated.
• Payback in quality crops, ease of operation, low maintenance, and compliance with environmental regulations.

43. Shade Cloths

44. Cooling pads
Higher cooling efficiencies with lower volumes of air allows use of smaller fans.

46. New Material on Maintaining Regulating Controls Inside the Greenhouse

47. Maintenance of Greenhouse Operations
Heating Systems / Temperature Check List:
Adequate clean fuel
Thermostats working properly
Fans, fan motors, and fan belts working properly
Cooling pads have adequate water
Clean pads
Shade cloths attached
Shade materials applied or removed depending on need.

48. Maintenance of Greenhouse Operations
Light Systems Check List:
Shade cloths attached or removed
Shade materials applied or removed depending on need
Light bulbs replaced as needed
Photocells and timers working properly

49. Maintenance of Greenhouse Operations
Watering Systems Check List:
Humidistats and fogging or mist systems working properly
Water lines and faucets not leaking
Adequate source of high quality water
Clean water

50. Maintenance of Greenhouse Operations
Sanitation Check List:
Control weeds around greenhouse
Prevent weeds (Be proactive)
Prevent insects, rodents, and diseases inside the greenhouse.

51. Review of Today’s Material
Which greenhouse maintenance category is most affected by controlling weeds, insects, and rodents?
Light
Moisture
Sanitation
D. Temperature

52. Review of Today’s Material
Which greenhouse maintenance category is most affected by controlling weeds, insects, and rodents?
Light
Moisture
Sanitation
D. Temperature

53. Heaters, fans, cooling pads, and ventilators are used in a greenhouse to control:
Light
Moisture
Sanitation
Temperature

54. Heaters, fans, cooling pads, and ventilators are used in a greenhouse to control:
Light
Moisture
Sanitation
Temperature

55. Moisture in a greenhouse is controlled by using:
Black cloths
Humidifiers
Insecticides
Lights

56. Moisture in a greenhouse is controlled by using:
Black cloths
Humidifiers
Insecticides
Lights

57. Light in a greenhouse is controlled by using:
Black cloth and bulbs
Foggers and humidifiers
Heaters and fans
Ventilators and cooling pads

58. Light in a greenhouse is controlled by using:
Black cloth and bulbs
Foggers and humidifiers
Heaters and fans
Ventilators and cooling pads

59. Next We Will Go Out and Inspect Our Greenhouse and List Problems.

60. There are more temperature related maintenance items than there are light related maintenance items.

61. Tensiometers - The substrate moisture is monitored in the plant root zone. The switching tensiometer can turn the irrigation system on when water is required. A trickle irrigation system delivers the water.

64. foggers