GREENHOUSES: Plastics and Their Characteristics

Plastic greenhouses can be heated as satisfactorily as glass ones; crops are of equal quality; construction costs per square foot are about one-sixth; in some areas they are assessed as temporary structures and carry low or no tax rates. OD74-202

Greenhouses	Comments
GREENHOUSE BLANKET: For Heat Conservation A sheet of plastic drawn horizontally just before sundown across the greenhouse about six feet above the ground to trap the warm air and reduce the cubic area requiring heat; to be withdrawn each sunrise. F82-156	0
GREENHOUSES: A Basic Law in Their Operation The taller the greenhouse the easier it is to operate. OD67-298	0
GREENHOUSES: Automatic By use of Envirorrdl designed for a fan heater of 2400 watts output at 10 amps, one evaporative cooler and a circulating fan; suitable for an area 12 ft. by 8 ft.; for details see AU87(l)-36	0
GREENHOUSES: Automation Electronic environmental control with modern technology without time clocks but with sensing and control devices and control equipment; refer to W9-115	0
GREENHOUSES: Best Construction Woods Redwood or cypress but the latter is hard to find; where wood contacts ground it should be soaked in copper napthanate preparation, which extends its usefulness by a few years. A72-807	0
GREENHOUSES: Cheap and Effective Construction details for a basic house sized 10ft by 8ft. by 8.25 ft. high; expandable type, refer to AU82-127	0
GREENHOUSES: Construction Design and details of a 32ft. long glass unit for an amateur's use incorporating below-ground floor, rain tanks, Insolshade bubble insulation, etc., refer to OR88-18;40For general culture in Canada, refer to A85-31; 1096	0
GREENHOUSES: Cool Growing Environment Design and construction of a unit for minimum night temperature of 50dF, a day minimum of 60dF and day maximum of 85dF; heaters, polyethylene lining, air movement, ventilation, dry area; for details oee OR87-51	0
GREENHOUSES: Coverings Heat loss per BTU per sq. ft. per hour at zero degrees F. is: glass -- 1.13; doubled glass -- 0.65; triple glass -- 0.47; PVC -- 0.92; Fiberglass -- 1.00; Acrylic (Plexiglass) -- 1.00; Acrylic doubled rigid -- 0.52; Polycarbonate doubled -- 0.62; Polyethylene film (2, 4, or 6 mil.) -- 1.15; Poly-film doubled -- 0.70; Mylar -- 1.05. Florists' rev. 1979 v.164-132	0
GREENHOUSES: Design and Construction Two-storey advanced design for intermediate to warm growing conditions as part of garage architecture; for details refer to A87-799	0
GREENHOUSES: Design Principles Nine major steps: checking the local building code; the design processes; drawings and more drawings; choosing the builders; reviewing every design idea and itemizing the problem points; analyzing decisions; project costs; and, final thoughts; refer to A87-729	0
GREENHOUSES: Electronic Controls Devices include a cool inlet fan, a hot air outlet fan, a fan heater, an overhead misting and watering nozzle system, an external roof-misting system, a silicon diode control and electronic thermometer, sensors, phototransistors, solenoid, humidistat, electronic clock, etc., for the technicians' delight.AU87(4)-15	0
GREENHOUSES: Energy Efficient Ten points emphasized for the Maryland area: the temperature below the earth frost line is 13 dC; solar energy is always available; a southern exposure is necessary; the sun's rays should strike the roof at 90 Deg. angle for Maryland; black absorbs heat; all side walls should be insulated; insulation on the outside of the foundation down to 46cm or more below line; a storage system is a necessity; temperature stability is important; utilizing a hillside; refer to Wll-115	0
GREENHOUSES: Epoxy Enamels as Paint on Wood Is used for boat bottoms, should do almost as well in greenhouses. A66-580	0
GREENHOUSES: Floors The ideal is a floor dug down to three feet, filled in with a foot of large stones and two feet of pebbles; concrete and dirt floors tend to lower humidity. OIg88Feb-3	0
GREENHOUSES: Foundations Constructed of Creosoted Railway Ties The creosote should be coated carefully with linseed oil; for added protection from the creosote fumes areas exposed on the inside should be covered with aluminum foil. A73-615	0
GREENHOUSES: Fumes -- Toxic Effect of Pesticide Smoke Their effects remain for about 12 hours; it is safe to enter 12 hours after using Plantfume #103. A78-403	0
GREENHOUSES: Glass Type Recommended A double-thick, regular, clear "B" quality glass is good. A64-975	0
GREENHOUSES: Heat Control Redistribution of the hot air in the apex of the house to the bench level is achieved by using the "Equal Heat" mechanism, for explanation refer to OR84-409	0
GREENHOUSES: Heating Transmission coefficients for materials; for a list of 34 materials and the degrees of heat loss; refer to OD71-192+ (See also Heating).	0
GREENHOUSES: Heat Loss Calculation A simple method: the heat loss in BTU's per hour is equal to the square feet of the glazed area X the temperature lift (raising greenhouse temperature above the average outside temperature) X 0.44 X 3.412; for a more sophisticated method refer to OD71-194	0
GREENHOUSES: In Canada Problems of light and temparatures as they affect culture and structures in special areas devised to provide optimum conditions, refer to Wll-347	0
GREENHOUSES: Indoor Urban Novelty Area size 20 by 30 ft. on the 12th floor of a New York City building; painting and sealing the apartment with epoxy paint and plastics, use of fiberglas, fertilizer proportioner, humidifier, four large 1000-watt sodium vapor bulb lamps, alternating warm and cool-white plus UHO fluorescent tubes, fans, pans to collect watering run-off and create humidity; an air-conditioner for summer; quite awesome. A83-1255	0
GREENHOUSES: Insulation Air-space Ideally, the space between outer and inner layers of a greenhouse cover should be approximately 1.5 inches thick, but spaces of three-quarters to eight inches are used; below three-quarters inch the effectiveness is rapidly lost. A64-548	0
GREENHOUSES: Maintenance and Safety Precautions Never work on the roof alone; never use white lead dissolved in gasoline for shading; never use gasoline when painting; cymbidium leaf-tips have inflicted many an eye-injury so wear protective goggles; break into two sides any double edged safety razor blades used for cutting flowers; do not store ammonium nitrate with fuel oil, etc. because contamination can produce an explosive; use protective goggles and a mask when spraying toxics. A72-328+	0
GREENHOUSES: Most Efficient Use of Sun's Radiation The Ritelite planthouse; has its glass surfaces opposed to the surface of the atmosphere; are fixed in "normal" position in mid and higher latitudes to approximate tropic light values; refer to OA75-215+	0
GREENHOUSES: Plans to Build A publication is usually available from your government college of agriculture which recommends plans. A72-412	0
GREENHOUSES: Plastic Lining for Insulation The most economical film is two-mil polyethylene which produces a slight shading effect. A65-52	0
GREENHOUSES: Plastic Linings for Insulation Still air is the best insulation, to achieve it use plastic linings of polyethylene about 2in. away from the inside of the roof; it is efficient; plastic bubbles material one inch size between two sheets of polyethene (as a sandwich) is most efficient. OR84-219	0
GREENHOUSES: Preferred Covering Glass allows for a maximum of light or of shading; next comes clear fiberglass; for a strong sun area opaline or a frosted fiberglass may be best. A72-1100	0
GREENHOUSES: Pressure-treated Lumber for Construction Avoid wood treated with creosote, pentachlorophenol or copper compounds; the non-toxic ones are fluorochrome, arsenate phenol, and chromated zinc chloride. A86-147	0
GREENHOUSES: Reflecting Light From North Wall Use bright aluminum foil and keep it algae-free; it probably exceeds reflection from a white painted wall. A65-53	0
GREENHOUSES: Roof of Corrugated Plastic Use one-sixteenth inch clear colorless plastic; the orientation of the corrugations is unimportant except to shed water and dirt most efficiently. A65-52	0
GREENHOUSES: Roof Slope Minimum Moisture can be made to run down rather than drip; 35% slope is probably the minimum and 40% is often used. A67-901	0
GREENHOUSES: Sanitation A program of cleaning, sweeping and disinfecting with bleach, Physan, Shield; a fungicide treatment of plants and greenhouse with Natriphene, Panogen or Tersan; refer to A66-375+Infestations of many pests originate on outside plants growing around, so the land should be cleared of growing things in the periphery. AH86-61Remove all decaying leaves; flowers and spilled compost from benches and floors; do not store potting media in the greenhouse; all organic materials favor fungal and bacterial growth. OD67-50	0
GREENHOUSES: Solar Design Types In Texas a 12ft. by 16 ft unit was partly submerged in the ground and is described with illustrations, diagrams, specifications and discussion of preferred ways and means; refer to A83-500	0
GREENHOUSES: Solar Lean-to Type In Massachusetts, a design with construction details for efficiency in operation; illustrations, plans; refer to A83-1031	0
GREENHOUSES: Solar Types A system incorporating a conservatory to trap efficiently solar energy, with reflectors to boost input through geometrically oriented windows; apertures and insulation methods; 70 genera housed; illus.; refer to A86-143	0
GREENHOUSES: Space Limitations Impose Changes Get rid of the poor plants in the collection; relocate the inanimate objects; use step benches for more pot space, use vertical space by means of mounted plants, for pot hangers, etc.; use floor space more effectively by filling in spaces along the benches and walls; create a mini-greenhouse adjaccent; example. A83-578	0
GREENHOUSES: Submerged A combined solar and sunken structure in Maryland has marry advantages; for complete details refer to A82-1141An "English" style, size 7 ft, by 9 by 5.5 deep; a huge success is the claim and economical to operate to boot; refer to A81-304; the same greenhouse added to. A81-562,, in Pennsylvania; another one in Texas: it saves energy,provides moderated temperatures. A81-385	0
GREENHOUSES: Sunlight and Automatic Control Use Saran roll screening arranged to raise or lower automatically depending on the amount of sunshine acting as a trigger on a thermostat; diagrams given; refer to A71-699+	0
GREENHOUSES: Unheated in San Francisco Growth and flowering may be delayed at a night temperature of about 50 dF (lO dC); if the temperature was lower the plants should be given some warmth or moved to a warmer area at critical times. A84-1061	0
GREENHOUSES: Warm Growing A discussion of location, size, shape, energy conservation, air movement, heating, automation, in New Zealand, refer to NZ86-82	0
GREENHOUSES: Weed Control on Gravel Floor Weeds growing from the soil under the gravel can be sprayed with Simazine 80W, or with Telvar, or with ordinary borax. A70-427; A71-609	0
GREENHOUSES: Western Red Cedar Construction For data on design, construction pointers, etc. refer to OR87-14 (England)	0
GREENHOUSES: Winterizing The heaters, whether electric, kerosene or gas, or oil should be checked; the structure should be examined for leaks; a double layer of plastic insulation should be installed for winter only, a heat conservation blanket should be installed, water should be checked and the air circulation proved out. F82-157	0
GREENHOUSES: Wood Treatment for Construction Creosote or pentachlorophenol should not be utilized due to their toxic fume release for years after; avoid copper compounds which are also toxic to orchids; use fluorchrome, arsenate of phenol, or, chroma ted zinc chloride. A86-147	0

Greenhouses

Comments

GREENHOUSE BLANKET: For Heat Conservation A sheet of plastic drawn horizontally just before sundown across the greenhouse about six feet above the ground to trap the warm air and reduce the cubic area requiring heat; to be withdrawn each sunrise. F82-156

GREENHOUSES: A Basic Law in Their Operation The taller the greenhouse the easier it is to operate. OD67-298

GREENHOUSES: Automatic By use of Envirorrdl designed for a fan heater of 2400 watts output at 10 amps, one evaporative cooler and a circulating fan; suitable for an area 12 ft. by 8 ft.; for details see AU87(l)-36

GREENHOUSES: Automation Electronic environmental control with modern technology without time clocks but with sensing and control devices and control equipment; refer to W9-115

GREENHOUSES: Best Construction Woods Redwood or cypress but the latter is hard to find; where wood contacts ground it should be soaked in copper napthanate preparation, which extends its usefulness by a few years. A72-807

GREENHOUSES: Cheap and Effective Construction details for a basic house sized 10ft by 8ft. by 8.25 ft. high; expandable type, refer to AU82-127

GREENHOUSES: Construction Design and details of a 32ft. long glass unit for an amateur's use incorporating below-ground floor, rain tanks, Insolshade bubble insulation, etc., refer to OR88-18;40For general culture in Canada, refer to A85-31; 1096

GREENHOUSES: Cool Growing Environment Design and construction of a unit for minimum night temperature of 50dF, a day minimum of 60dF and day maximum of 85dF; heaters, polyethylene lining, air movement, ventilation, dry area; for details oee OR87-51

GREENHOUSES: Coverings Heat loss per BTU per sq. ft. per hour at zero degrees F. is: glass -- 1.13; doubled glass -- 0.65; triple glass -- 0.47; PVC -- 0.92; Fiberglass -- 1.00; Acrylic (Plexiglass) -- 1.00; Acrylic doubled rigid -- 0.52; Polycarbonate doubled -- 0.62; Polyethylene film (2, 4, or 6 mil.) -- 1.15; Poly-film doubled -- 0.70; Mylar -- 1.05. Florists' rev. 1979 v.164-132

GREENHOUSES: Design and Construction Two-storey advanced design for intermediate to warm growing conditions as part of garage architecture; for details refer to A87-799

GREENHOUSES: Design Principles Nine major steps: checking the local building code; the design processes; drawings and more drawings; choosing the builders; reviewing every design idea and itemizing the problem points; analyzing decisions; project costs; and, final thoughts; refer to A87-729

GREENHOUSES: Electronic Controls Devices include a cool inlet fan, a hot air outlet fan, a fan heater, an overhead misting and watering nozzle system, an external roof-misting system, a silicon diode control and electronic thermometer, sensors, phototransistors, solenoid, humidistat, electronic clock, etc., for the technicians' delight.AU87(4)-15

GREENHOUSES: Energy Efficient Ten points emphasized for the Maryland area: the temperature below the earth frost line is 13 dC; solar energy is always available; a southern exposure is necessary; the sun's rays should strike the roof at 90 Deg. angle for Maryland; black absorbs heat; all side walls should be insulated; insulation on the outside of the foundation down to 46cm or more below line; a storage system is a necessity; temperature stability is important; utilizing a hillside; refer to Wll-115

GREENHOUSES: Epoxy Enamels as Paint on Wood Is used for boat bottoms, should do almost as well in greenhouses. A66-580

GREENHOUSES: Floors The ideal is a floor dug down to three feet, filled in with a foot of large stones and two feet of pebbles; concrete and dirt floors tend to lower humidity. OIg88Feb-3

GREENHOUSES: Foundations Constructed of Creosoted Railway Ties The creosote should be coated carefully with linseed oil; for added protection from the creosote fumes areas exposed on the inside should be covered with aluminum foil. A73-615

GREENHOUSES: Fumes -- Toxic Effect of Pesticide Smoke Their effects remain for about 12 hours; it is safe to enter 12 hours after using Plantfume #103. A78-403

GREENHOUSES: Glass Type Recommended A double-thick, regular, clear "B" quality glass is good. A64-975

GREENHOUSES: Heat Control Redistribution of the hot air in the apex of the house to the bench level is achieved by using the "Equal Heat" mechanism, for explanation refer to OR84-409

GREENHOUSES: Heating Transmission coefficients for materials; for a list of 34 materials and the degrees of heat loss; refer to OD71-192+ (See also Heating).

GREENHOUSES: Heat Loss Calculation A simple method: the heat loss in BTU's per hour is equal to the square feet of the glazed area X the temperature lift (raising greenhouse temperature above the average outside temperature) X 0.44 X 3.412; for a more sophisticated method refer to OD71-194

GREENHOUSES: In Canada Problems of light and temparatures as they affect culture and structures in special areas devised to provide optimum conditions, refer to Wll-347

GREENHOUSES: Indoor Urban Novelty Area size 20 by 30 ft. on the 12th floor of a New York City building; painting and sealing the apartment with epoxy paint and plastics, use of fiberglas, fertilizer proportioner, humidifier, four large 1000-watt sodium vapor bulb lamps, alternating warm and cool-white plus UHO fluorescent tubes, fans, pans to collect watering run-off and create humidity; an air-conditioner for summer; quite awesome. A83-1255

GREENHOUSES: Insulation Air-space Ideally, the space between outer and inner layers of a greenhouse cover should be approximately 1.5 inches thick, but spaces of three-quarters to eight inches are used; below three-quarters inch the effectiveness is rapidly lost. A64-548

GREENHOUSES: Maintenance and Safety Precautions Never work on the roof alone; never use white lead dissolved in gasoline for shading; never use gasoline when painting; cymbidium leaf-tips have inflicted many an eye-injury so wear protective goggles; break into two sides any double edged safety razor blades used for cutting flowers; do not store ammonium nitrate with fuel oil, etc. because contamination can produce an explosive; use protective goggles and a mask when spraying toxics. A72-328+

GREENHOUSES: Most Efficient Use of Sun's Radiation The Ritelite planthouse; has its glass surfaces opposed to the surface of the atmosphere; are fixed in "normal" position in mid and higher latitudes to approximate tropic light values; refer to OA75-215+

GREENHOUSES: Plans to Build A publication is usually available from your government college of agriculture which recommends plans. A72-412

GREENHOUSES: Plastic Lining for Insulation The most economical film is two-mil polyethylene which produces a slight shading effect. A65-52

GREENHOUSES: Plastic Linings for Insulation Still air is the best insulation, to achieve it use plastic linings of polyethylene about 2in. away from the inside of the roof; it is efficient; plastic bubbles material one inch size between two sheets of polyethene (as a sandwich) is most efficient. OR84-219

GREENHOUSES: Preferred Covering Glass allows for a maximum of light or of shading; next comes clear fiberglass; for a strong sun area opaline or a frosted fiberglass may be best. A72-1100

GREENHOUSES: Pressure-treated Lumber for Construction Avoid wood treated with creosote, pentachlorophenol or copper compounds; the non-toxic ones are fluorochrome, arsenate phenol, and chromated zinc chloride. A86-147

GREENHOUSES: Reflecting Light From North Wall Use bright aluminum foil and keep it algae-free; it probably exceeds reflection from a white painted wall. A65-53

GREENHOUSES: Roof of Corrugated Plastic Use one-sixteenth inch clear colorless plastic; the orientation of the corrugations is unimportant except to shed water and dirt most efficiently. A65-52

GREENHOUSES: Roof Slope Minimum Moisture can be made to run down rather than drip; 35% slope is probably the minimum and 40% is often used. A67-901

GREENHOUSES: Sanitation A program of cleaning, sweeping and disinfecting with bleach, Physan, Shield; a fungicide treatment of plants and greenhouse with Natriphene, Panogen or Tersan; refer to A66-375+Infestations of many pests originate on outside plants growing around, so the land should be cleared of growing things in the periphery. AH86-61Remove all decaying leaves; flowers and spilled compost from benches and floors; do not store potting media in the greenhouse; all organic materials favor fungal and bacterial growth. OD67-50

GREENHOUSES: Solar Design Types In Texas a 12ft. by 16 ft unit was partly submerged in the ground and is described with illustrations, diagrams, specifications and discussion of preferred ways and means; refer to A83-500

GREENHOUSES: Solar Lean-to Type In Massachusetts, a design with construction details for efficiency in operation; illustrations, plans; refer to A83-1031

GREENHOUSES: Solar Types A system incorporating a conservatory to trap efficiently solar energy, with reflectors to boost input through geometrically oriented windows; apertures and insulation methods; 70 genera housed; illus.; refer to A86-143

GREENHOUSES: Space Limitations Impose Changes Get rid of the poor plants in the collection; relocate the inanimate objects; use step benches for more pot space, use vertical space by means of mounted plants, for pot hangers, etc.; use floor space more effectively by filling in spaces along the benches and walls; create a mini-greenhouse adjaccent; example. A83-578

GREENHOUSES: Submerged A combined solar and sunken structure in Maryland has marry advantages; for complete details refer to A82-1141An "English" style, size 7 ft, by 9 by 5.5 deep; a huge success is the claim and economical to operate to boot; refer to A81-304; the same greenhouse added to. A81-562,, in Pennsylvania; another one in Texas: it saves energy,provides moderated temperatures. A81-385

GREENHOUSES: Sunlight and Automatic Control Use Saran roll screening arranged to raise or lower automatically depending on the amount of sunshine acting as a trigger on a thermostat; diagrams given; refer to A71-699+

GREENHOUSES: Unheated in San Francisco Growth and flowering may be delayed at a night temperature of about 50 dF (lO dC); if the temperature was lower the plants should be given some warmth or moved to a warmer area at critical times. A84-1061

GREENHOUSES: Warm Growing A discussion of location, size, shape, energy conservation, air movement, heating, automation, in New Zealand, refer to NZ86-82

GREENHOUSES: Weed Control on Gravel Floor Weeds growing from the soil under the gravel can be sprayed with Simazine 80W, or with Telvar, or with ordinary borax. A70-427; A71-609

GREENHOUSES: Western Red Cedar Construction For data on design, construction pointers, etc. refer to OR87-14 (England)

GREENHOUSES: Winterizing The heaters, whether electric, kerosene or gas, or oil should be checked; the structure should be examined for leaks; a double layer of plastic insulation should be installed for winter only, a heat conservation blanket should be installed, water should be checked and the air circulation proved out. F82-157

GREENHOUSES: Wood Treatment for Construction Creosote or pentachlorophenol should not be utilized due to their toxic fume release for years after; avoid copper compounds which are also toxic to orchids; use fluorchrome, arsenate of phenol, or, chroma ted zinc chloride. A86-147

GREENHOUSES: Plastics and Their Characteristics

by Robert M. [Bert] Hamilton (Compiler)

Originally published in The Orchid Doctor in 1980 and 1988

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