NEW! Update from Scott (separate page).
Sherry,
Here is the write-up on my greenhouse I said I would send. I have also sent some photographs. Sorry it has taken so long. Hopefully the visitors to your website will find it informative. When I started with the greenhouse, information and resources were difficult to locate and a first hand account of trials, errors, and successes in a home greenhouse would have been welcome.
One thing I have learned is that every greenhouse is different. What works for one may not work for another. The control and operation of my greenhouse is an ongoing challenge. It varies in difficulty depending on what I want to grow and how much money I want to spend. It can take a lot of trial and error.
I have been accused (jokingly) of taking the fun out of a greenhouse by paying too much attention to the controls. I do enjoy the challenge of making it run efficiently, as much as I enjoy growing the plants. However, it is just a matter of time before I am satisfied with its operation. Then I will turn to growing plants and trying to make a profit with it.
I will start by giving a brief background and description of the greenhouse Then I will describe the renovation that was done. I have included each control system's construction and operation including the revisions I found necessary. At the end I have included a list of books I have found helpful on the subject of greenhouses.
To save money I have done all the labor, including the plumbing and electrical, with advice and an occasional hand from my dad. He also contributed a considerable amount of materials.
---Scott H. West Lafayette, Indiana
The greenhouse is an "extra" that was included with the house I purchased in July of 1993 (I was 28 with no greenhouse experience). It was originally purchased in 1977 and erected by a local greenhouse/nursery. I have not been able to determine the manufacturer or the distributor (Alcoa?, Lauer?). The greenhouse strongly resembles a larger version of the one pictured in the lower right hand corner on the back cover of the ORTHO book on greenhouses. The cost in 1977 was between three and four thousand dollars. I do not know what this setup would cost today. If anyone recognizes this greenhouse from my descriptions I would appreciate any information they could relay. It would be real interesting to hear from someone who has one. Unfortunately, my email address is through work. To avoid sorting through personal mail looking for client mail I am withholding it. However, for those with a printer, envelope, and stamp, I can be reached at P.O. Box 2785, West Lafayette, Indiana 47906.
When I took possession of the property, the greenhouse was in a state of disrepair due to the previous owner's health. The caulking was falling out, staging was rotted, automatic vent inoperable, etc. There were also a large number of plants including lots of geraniums, bromeliads, and cacti. There were also a few hibiscus, clivia, several amaryllis (hippeastrum), begonias, and a few freesias and lilies. Aloe vera, spider plants, kalanchoe, and shrimp plants were rooted in the pea gravel floor (not just existing, they were multiplying). Several hanging plants were also there, including spider plants, zebrina, burrow's tail, teddy bear vine, and hoya. At the east end there was a large bougainvillea and in the center there stood an eight foot tall palm tree that had rooted through its half barrel into the ground. It had to be cut out with a chainsaw.
The greenhouse's dimensions are 14 feet wide by 24 feet long with a peak of nine feet. Side walls are six feet high at the eaves, this includes a cement block knee wall two feet in height which rests on a 12" wide poured cement foundation. There is about 300 square feet of floor area.
The greenhouse is oriented with the longest dimension east and west with an attached shed (20'x24') on the east side. The attached shed does shade the greenhouse in the mornings preventing full sun exposure until noon. There is a large Norway spruce at the northwest corner of the greenhouse offering some windbreak from the north (prevailing winds are from the southwest). One hundred feet to the southwest begins the most significant windbreak, a south running row of large pine trees.
My house, a ranch, is located 70 feet directly south of the greenhouse. To the north is a 20 acre field. In spite of the trees, I still catch a lot of wind from the west-southwest. For additional windbreak, I have planted four arborvitae eight feet north of the greenhouse and eight arborvitae extending the row of pine trees to the north (presently these are only 3 to 4 feet tall).
The first step was to clean out, repair, and insulate the greenhouse. This took place late 1993 to early 1994. I disposed of many plants, gave many away, and what I wanted went into the house. The shade was removed ([the former owner] used corrugated fiberglass which fit inside the glass and rested on the aluminum "I" frame) and the glass was cleaned. Then the staging was removed (these were constructed of cedar 1X6 boards with metal pipe supports). All salvageable wood was saved.
All plants and roots were removed from the pea gravel floor with a garden rake and a shovel. After repairing the mortar, the cement block knee wall was painted inside and out with white "DRYLOC" brand masonry waterproofer. I then dug a one foot deep trench inside the perimeter of the greenhouse and buried a 12 inch wide strip of 1 inch thick Styrofoam insulation. Using this same extruded polystyrene (R5), I lined the inside of the knee wall using silicone caulk "globs" as adhesive.
All the glass was sealed with twenty-five year, clear silicone sealant. The vertical seams I did from the outside and the horizontal seams from the inside. This took about 14 tubes of sealant. I weather-stripped both of the ridge vents and the west door with foam weather-stripping (open cell on the door and closed cell for the vents).
All five motors also had to be removed from the automatic vent. They had to be disassembled, cleaned, and rewired. This completed the renovation of the frame and attached accessories except for the gas heater that would wait two years.
I rebuilt all the staging (benches) using the salvaged wood and some other rough sawn cedar that was left in the shed. Along the north wall of the greenhouse I have one bench. This bench rests directly on water barrels and on shelf brackets attached to the side of the shed. Its dimensions are about 23 feet long by three feet wide. This bench was built in two sections. Each section was constructed roughly as follows: leaving a small gap between them, six cedar 1x6's of the same length were laid side by side. They were fastened together on the bottom with 1x3 cedar slats laid across their width. Using drywall screws, the 1x3 was screwed to each 1x6 (pilot holes were drilled first). Cedar 1x3's also form a "rim" around each bench. I tried to keep all screws on the bottom of the benches so water could not pool around them and slowly rot the wood.
Five additional benches were constructed in the same manner, all three feet wide. Their lengths vary from four feet to seven feet. All five of these can be moved. They use cement blocks as supports. To set up these benches I level the pea gravel with a rake and a four foot level, then the cement blocks are stacked to the desired height at each end (plumb and level). The bench is then laid on the blocks with the 1x3 slats on the bench bottoms contacting the blocks. All benches were treated with copper naphthanate based wood preservative, allowed to dry, and then rinsed prior to use. This represents approximately 150 square feet of bench space.
I prefer many smaller benches over a few large ones because of the flexibility you are allowed in reorganizing the greenhouse. If you are constructing your own benches, be sure to leave the gap between the boards. This allows water, potting soil, leaves and dead bugs to fall through making cleaning easier.
The glazing is single pane, double strength (1/8" thick) glass, approximately 1.5 feet square which is seated into caulk and held with clips to the extruded aluminum frame. Glass at the eaves is curved; it is difficult to find and expensive. The glass has withstood heavy hail 7/8" in diameter and winds of 60 mph with no breakage. On rare occasions, cracks have appeared with no apparent cause. These were repaired by running a bead of 25 year, clear silicone on both the inside and outside of the cracks.
I have had to replace only two panes in three years. These broke when the manual vent was left partially open and a wind gust lifted the vent (there are a few inches of slop in the gearbox that opens the vent). When the vent dropped it broke one of the cast aluminum "elbows' that supported it, flexing the vent and breaking two panes. These two panes created an amazing amount of litter both in and around the greenhouse. Custom cut double strength glass cost me about $4 per pane. The glass is available locally.
I have had little trouble with "hotspots" caused by glass glazing, but I do understand the benefits of light diffusion that proponents of polycarbonate and fiberglass glazing systems always mention. If I were building a greenhouse I would put polycarbonate on the roof (because it is unbreakable) and double strength, thermopane glass on the walls (I like to be able to see both in and out of the greenhouse).
For shading in 1994, I used a product called Varishade 2 (Charley's [Greenhouse Supply, 1-800-322-4707] is a supplier). This product is diluted with water and applied with a paint roller. I had mixed results with this product.
What I liked: 1. It looked clean. It is opaque white when dry and clear when wet. 2. It cut down on light very little while eliminating some of the heat. I think it actually increased the light inside due to diffusion. 3. It is not very expensive.
What I did not like: 1. I could not reproducibly apply it. Sometimes it went on consistent and stayed on long. Other times it looked splotchy and came off in patches the first rain. Once I even washed the entire greenhouse with a sponge mop before the shade was applied. This did not seem to help. The manufacturer, Solar Sunstill Inc., had no answers. 2. Hail storms were bad news. The summer of 1994 we had several strong isolated storms that brought heavy rain and hail. One storm dropped four inches of rain in one and a half hours and HEAVY hail the diameter of a quarter. This strips the shade off in no time.
In theory, you can apply the shade on the inside of the glass that would eliminate the stripping caused by storms, but I have had inconsistent results with this also. I wrote the manufacturer asking what effect hard versus soft water as a diluent would have on the product, if the pH of the water could have an effect, preferred application temperatures, etc. and got no reply.
For shade in 1995, I decided to try polypropylene shade fabric (A.M. Leonard [1-800-543-8955] is a supplier). I purchased a sheet 24 feet long by 8 feet wide in 30% density. This I installed on the exterior of the south side of the greenhouse beginning below the vent. To attach it to the greenhouse I drilled eight holes into the aluminum frame for 1/2 inch eye bolts. Between the eye bolts I tied cord that acts as a "frame" for the shade fabric. Then using "Grip-Clips"(A.M. Leonard) the fabric was attached in its frame. The north side and the west end were shaded with Varishade.
Compared to the greenhouse with the Varishade only: there was more heat to contend with and it seemed darker. I have been afraid to go to heavier shade (for more cooling) since the tomatoes seemed to stretch with the 30% fabric (this may have been due to other variables). The fact that I only had to install the shade fabric once far outweighed any negative factors. This past summer (1996), I had 30% fabric on the north and south with Varishade only on the ridge vents and the west end.
There are two ridge vents that run the entire length of the greenhouse (both are 1.5 feet wide). The vent on the north side is thermostatically controlled with five electric motors. When the thermostat triggers the motors, they open the vent and hold it while power is on. When the thermostat turns off, the weight of the vent pushes it closed. The rate at which it closes is controlled by the drag of the motors. This vent is mainly used in spring when the outside air temperature is too cool to leave a vent open and the sun is strong enough to drive the inside temperatures above those that seedlings can withstand.
The vent on the south is manually operated by a chain/wheel gear motor. In the late spring and early fall it becomes a ritual to open the vent in the morning and close it in the evening. During the summer, the manual vent can be left open day and night. If heavy rain or strong winds are predicted, the vent is closed. Other than the ridge vents, my only ventilation is through the windows of the doors and one of these is marginally effective since it opens into the shed. More ventilation would be useful.
[Scott does not mention using a fan to assist ventilation. I recommend keeping a fan running at all times to circulate the air. This is especially important in winter when greenhouses are sealed up. The fan ensures that the plants will have use of any available carbon dioxide which is usually in short supply in winter months because less outside air is allowed into the greenhouse. Circulating the air also helps prevent fungal diseases. The fan in Sherry's (actual) greenhouse is inside (not installed in an outside wall) so no cold outside air is brought in while running it. One reason for that is that I live in an urban area, and a wall-installed fan would disturb the neighbors.]
For a passive solar heat sink I obtained ten, 45 gallon, black plastic barrels. These were salvaged from industry, originally containing caustic sodium and potassium hydroxides (lye). They were cleaned and rinsed, lined up along the north wall starting at the west end, and filled with water after they were leveled. This left room for two barrels next to the shed, but I only had ten. I use this extra space as storage for several six and eight inch clay pots that stack resting on small cement blocks.
It is difficult to determine what contribution these barrels make to the heat in the greenhouse. I have only recently started tracking the temperature of the water with an averaging thermometer in the center barrel. The actual probe is long enough to coil around inside the barrel so the temperature it reads is an average of the entire barrel. The temperature has been fluctuating between 57 degrees F. (after a warm, sunny day) and 52 degrees F. (after two days with little sun). I have never seen the temperature rise more than 4 degrees F. in one day. The water temperature is dropping below the minimum air temperature (56ºF) which bothers me. I think this is due to the fact that I rested the barrels directly on the pea gravel floor. The barrels should be drained and refilled on an insulated platform.
Even now (November), there is excess heat on sunny days. I have seen 112 degrees F. twice this month which is too stressful for the plants. When I get the shed remodeled, I plan on having thermostatically controlled vents near the top and bottom of the greenhouse in the wall of the shed. Then when it gets too hot, I can circulate the heat into the shed. I will also probably convert the water barrels from a passive heat sink into an active solar collector next year. As a passive collector they are too inefficient.
The use of an underground thermal mass for heat storage has crossed my mind.
I have access to a backhoe so the excavation would be no problem. It seems like
there are a lot of factors that would have to be taken into consideration to
make it work. The thermal mass (composition, mass, and surface area) would probably
have to be matched to the temperature and flow rate of the forced air used to
charge the mass. The hole in the ground would also have to be made watertight.
If it ever filled up you would have a mess.
I heat with an 80,000 Btu (input) gas unit heater that hangs near and is vented through the west end. This was originally fueled by propane, but this spring I had natural gas service ran to the shed. Gas is plumbed from the meter in 1 inch black pipe, through the upstairs of the shed. I have another 80,000 Btu unit heater that I will eventually install in the shed. The pipe is reduced to 3/4 inch black pipe before it goes through the wall of the shed (about seven feet high) into the greenhouse. In the greenhouse the pipe is attached to the overhead frame with pipe hangers approximately every six feet. At the west end of the greenhouse the pipe is further reduced to 1/2 inch before it enters the regulator just prior to the heater. To convert the heater to natural gas, I had to drill out the burner and pilot orifices. Then, after the plumbing was inspected and the gas was turned on, it was necessary to adjust the regulator to get the burners to burn correctly.
The previous owner heated with propane gas. I was told the first year they heated with no polyethylene sheet over the exterior and the cost was $1500 (North-central Indiana winters in zone 5, average annual low is -20 degrees F.). With a 4 mil polyethylene "bag" in place for the heating season the cost was $75 a month budget to heat for about six months to 50 degrees F. minimum. These figures are for the winter of 1992-1993 ([the previous owner] may have been heating the shed too). My neighbors tell me that her plastic wrap job was sloppy so she probably had drafts. I hope to be able to heat the entire winter for no more than $500.
This is the first winter I will heat the greenhouse. In previous years, all the plants I wanted to save were moved into the house in the fall, and then returned to the greenhouse in the spring. To make the greenhouse more economical to heat I have insulated the inside of the north wall and two thirds of the north roof with Dow brand Styrofoam board (1" thick = R5). I have also wrapped the greenhouse with 4 mil polyethylene plastic. Both the plastic and the insulation will be removed after winter. The plastic is held down with cement blocks sitting on the plastic around the perimeter of the greenhouse. Polypropylene cords go over the greenhouse and tie to the cement blocks (this keeps the plastic from billowing up in the wind). If you try this, be sure to anchor the plastic securely. If a strong wind were to get underneath and pick it up it could cause damage to the greenhouse. You should also allow for contraction and expansion of the plastic when you install it.
Heating costs so far for 1996-1997 (56 degrees F. minimum): (This is the actual cost of gas consumed. It does not include the gas companies monthly charge for service or the fixed cost of the plastic and insulation).
August 5 - September 5 = $6.20
September 5 - October 5 = $8.26
October 5 - November 5 = $20.65
(The greenhouse was insulated October 15 and plastic installed October 25).
November 5 - November 16 = $15.83
If costs get excessive then I will lower the minimum temperature to 50 degrees Fahrenheit and install greenhouse bubble insulation on the interior of the greenhouse. So far it looks affordable but we have not had many temperatures below 20 degrees F. Cold, cloudy days with low temperatures near 20 degrees F. and high temperatures near 32 degrees F. cost under $2 for heat.
(All wiring is 12 gauge copper - 2 conductor with ground)
The original electrical service was a single 110 volt circuit off a fusebox in the shed. I replaced the fusebox (a 220 volt subpanel off the main in the house) with a breaker box and rewired the circuit to the greenhouse (using a 20 amp breaker). This circuit, call it "A" is split four ways in a box on the wall of the shed ("A" splits into A1, A2, A3, and A4).
A1 leads through a line level timer to two high pressure sodium lights. A2 leads through a thermostat and a humidistat to a short cycle timer that controls a heavy duty solenoid (S1) in the misting circuit. A3 is the misting circuit. It runs through the solenoid (S1) controlled by A2 to the water solenoid valve (S2). A2 and A3 are separated by S1 because the short cycle timer was salvaged and its electrical specifications are unknown. I decided to be safe and isolate it from the water solenoid (S2) which draws more current than S1. A4 is the original circuit. A4 is split three ways. A4-1 controls two switched eight foot (two bulbs) fluorescent fixtures I have hanging near the peak.
Originally, the greenhouse had two incandescent bulbs for light. I replaced the bulbs with screw in outlets where the fluorescents are plugged. A4-2 runs through a switch to a thermostat then to the five motors that control the automatic vent. A4-3 is power to the unit heater and two outlets (currently only one of these is GFI). All wiring in the greenhouse is in overhead conduit except for the thermostats and humidistat that are 3 to 4 feet from the ground.
To extend the photoperiod during winter I have two high pressure sodium lights. These are hanging about 6.5 feet from the floor. I think they are only 150 watts each, but they seem much brighter than that. Right now the sun sets around 6:00 pm. The lights are on a timer to come on at 5:30 pm and shut off at 9:30 pm. Even though their wattage is low, I am still getting good growth and fruiting from the tomato plants. These lights put off a nasty, yellow light that hurts my eyes. The only way I can work in the greenhouse at night is if I have the fluorescent lights on to "tone down" the sodium lights.
[In Sherry's greenhouse, I use a 1000 watt metal halide light. It is a full spectrum light, so appears more like sunlight and is comfortable to work around. I still have one fluorescent fixture installed as a work light if the metal halide light is not already on. Metal halide lights take a few minutes to warm up to full intensity. After being turned off, they should cool completely before being turned on again.]
The shed is actually the original house on the property so it already had plumbing and a septic tank. The previous owner ran a garden hose from inside the shed to the greenhouse for water. This was inconvenient so I plumbed water through the wall of the shed using 1/2 " galvanized pipe. Once in the greenhouse the pipe "T"s into two branches (B1 and B2). B1 goes through a ball valve to the water solenoid valve of the misting system. Beyond the solenoid the water runs in a length of garden hose (this allows repositioning of the misting units as desired). At the end of the garden hose is another "T" which branches into M1 and M2. M1 and M2 are identical. Each goes through a ball valve (so I can turn off half of the mist if necessary) which is attached directly to the misting unit.
Each misting unit is made from sixteen feet of 1/2" PVC pipe with pipe saddles and Flora Mist Fogger misting nozzles (Mellingers [216-549-9861]) every 4 feet. These nozzles deliver 4 gallon per hour at 35 psi water pressure. B2 goes through a ball valve to a "Y" with shutoffs. This is where the hoses originate. Each hose is 30 feet long with another shut off at the attachment end and each serves one side of the greenhouse.
I tried using a siphoning valve on one of the hoses for fertilizer but found it temperamental. Instead, I have a porcelain tub that I use for mixing large batches of fertilizer. It has a spigot on the bottom, making it easy to fill a watering can. I only have to mix fertilizer once every two weeks.
The construction of the misting system is described above in the plumbing section. I installed the misting system to cool the air, but it drenched the greenhouse in the process. I have settled for maintaining the humidity so the plants do not transpire so much water. In the summer, the system is set to mist for 38 seconds (the shortest "on" cycle my timer allows) once every 10 minutes while the temperature is above 85 degrees F. This setting allows the greenhouse to dry a reasonable amount in the evenings after it has cooled. With the humidistat set at 40%, I can prevent the system from misting while there is sufficient humidity even if the temperature is above 85 degrees F. (this is most likely to happen during winter).
When first installed I had the misting units above the plants (6.5 feet high). This worked fine but I use well water that has a lot of rust and dissolved minerals. Over the course of one summer the plants, benches, barrels, and some windows accumulated a significant buildup of scale deposit. To prevent this, I have moved the misting system to underneath the benches. I have to clean the misting nozzles monthly with a straight pin due to sediment in the lines.
In my greenhouse, a good misting system is absolutely necessary to make up for the high temperatures that go along with poor ventilation. [In Sherry's greenhouse, particularly in summer, I find also that a misting system is essential. I have good ventilation, but when air temperatures are above 100 degrees Farenheit, it doesn't help much to cool the greenhouse to the temperature of the outside air. The mist system is able to keep the greenhouse air at or below 85 degrees.]
Watering can also be reduced since the plants do not transpire as much. The first summer I tried combating high temperatures with a powerful fan, but many plants were severely wilted by the time I got home from work. With the misting system, all I need is a small oscillating fan set on low to help dry the floor. I have had very little trouble with wilted plants since installing the misting system.
The Greenhouse EffectDuring February and March of 1994, I consistently kept good, accurate data concerning temperatures inside and outside the greenhouse, weather conditions, etc. At that time there were no plants involved so the greenhouse could get as hot as it wanted. The barrels were in place but there was no polyethylene cover, no insulation other than in the floor and around the knee wall, and no active source of heat. Heat loss was mainly due to conduction through the nearly 650 square feet of single pane glass.
Heat gain during days with NO clouds: Over the period studied I recorded 10 days as 100% sun and for six of these there was no ventilation (greenhouse sealed). For the six days, the average temperature increase over the outside high was 48 degrees F. with a relative standard deviation (RSD) of +/- 15%. The greatest increase was 61 degrees F. The outside high temperatures ranged from 29 degrees to 48 degrees F. The data suggested that the temperature gain is independent of outside temperature; however, it was not a constant. I suspect the variable is wind speed, i.e., higher wind speed = greater heat loss through glass = lower temperature increases. These results were confirmed in February and March of 1995.
Currently, with the Styrofoam insulation and polyethylene cover (mentioned in the paragraph on heating), I am seeing temperature gains of 75 degrees F. on clear, sunny days. Like everyone, I would like to collect this heat and redistribute it at night. After a few more years of experimenting maybe I will be successful.
Heat gain during days with 100% clouds (these were dark, dismal days): Over the period studied I recorded six days that met this criteria and one day I vented (I was probably painting). For the five days that remained, the average temperature gain was 17 degrees F. with an RSD of +/- 15%. Again, there is no direct correlation between outside temperature and temperature gain, and wind speed was probably a factor.
Heat retention overnight: low temperatures in the greenhouse averaged 6 to 7 degrees F. above the outside lows. The smallest temperature difference was 1 degree F. and the greatest 7 degrees F. Some points to keep in mind here: 1. This greenhouse is not a "solar greenhouse" by design. A solar greenhouse should have a smaller glazing to inside surface area ratio, with the north side well insulated and a larger heat sink. 2. The greenhouse was empty (no plants). 3. Without a recording thermometer and data before and after the addition of water barrels it is difficult to determine the heat sink's contribution. I am sure the barrels are not capable of maintaining heat through the night.
I have had trouble with red spider mites, aphids, tomato horn worms, mice, and one chipmunk. I have only seen a whitefly once. [How many greenhouse gardeners can say that?]The chipmunk and mice were taken care of with traps. The main way I control insect pests is by not growing plants that seem susceptible to them. I no longer grow impatiens or feverfew because of aphids and avoid greenbeans because of spider mites.
Surprisingly, I have had very little problem with tomato horn worms on the tomato plants. The worms seem to prefer pepper plants including chile peppers. It is amazing how fast these worms appear and how much they eat. To control them I just pick them off and throw them outside. I consider them a minor problem.
If I have to spray, I prefer to use Safer Insecticidal Soap. The previous owner had an arsenal including Kelthane, Diazanon, Nicotine, Malathion, Chlordane, and Sevin. On very rare occasions I have used Kelthane, Diazanon, and Black Leaf 40 (Nicotine) but only Kelthane on vegetables (once).
In the summer the greenhouse attracts a lot of wasps. I leave them alone unless they are nesting where I can not avoid them. I have knocked wasps down with Insecticidal Soap but it is not as quick as Raid aerosol.
Here is a short list of some of the accessories I had a difficult time finding for a reasonable price.
Max/min thermometer. I bought a digital one that has a memory for temperature and humidity extremes. Available from Radio Shack. I have seen the same one in popular greenhouse supply catalogs for nearly twice the money.
Propagation mat. I bought a large propagation mat (22x44 inches) and a thermostat from A.M. Leonard (1-800-543-8955). They offer three sizes at prices that are difficult to beat.
Misting nozzles I bought 4 gallon per hour nozzles (too large for cooling)and pipe saddles from Mellinger's (1-216-549-9861). They also have a large selection of plants and stuff. Get theirs if you like to browse through catalogs. An excellent source for various misting supplies is Seasons Irrigation Supply Co. (1-800-396-0100). They have just about everything you could need for plumbing water systems in a greenhouse.
Shade fabric. I purchased Knitted Shade Cloth by DeWitt from A.M. Leonard (1-800-543-8955). They have two different brands ranging in density from 30% to 92%.
I have found all of the following books helpful and routinely go back to them.
Greenhouse Gardener's Companion. Shane Smith. Fulcrum Publishing,
1992.
The best all around home greenhouse book I have found. It includes greenhouse
culture requirements for many vegetables and flowers.
Ball Redbook - Greenhouse Growing. 15th edition. Vic Ball, editor. Geo.W. Ball Publishing. This book is targeted toward the large retail grower. It gives specific requirements for the culture of several retail crops and covers some of the latest technology for greenhouse environmental control. Some interesting topics include root zone heating (anyone planning a greenhouse should look into this as a way to save money) and cool day/warm night technology.
The Complete Book of the Greenhouse. 4th edition. Ian G. walls. [1988 and 1991.] Ward Lock Limited, London. It covers the greenhouse as well as plant culture and includes a good chapter on tomatoes. [The 5th edition, which I have, was published in 1993.]
Greenhouses- Planning, installing, and using greenhouses. 1991. Ortho Books. This is an excellent book almost entirely devoted to the construction, operation , and control of a greenhouse. There are lots of photographs. On the back cover, lower right hand corner there is a picture of a smaller version of my greenhouse (this same picture appears on page 79). I would love to know who the manufacturer is. Anyone know?
Time-Life Gardeners Guide. Greenhouse Gardening. Time- Life Books, Alexandria, Virginia. Kind of brief on greenhouse structures. Gives brief culture requirements and light requirements of several ornamentals and vegetable plants in foot-candles.
Be Your Own Greenhouse Expert. Dr. D.G. Hessayon. 1990. pbi Publications, England. [This book was republished in 1994 by Expert Books under the title The Greenhouse Expert.]
The American Horticultural Society Encyclopedia of Gardening.
1993. Dorling Kindersley, Inc. New York, NY. This is an excellent book on
gardening that includes a good chapter on greenhouses.
[Sherry's Greenhouse visitors please note: If you have matters to discuss with Scott directly regarding his greenhouse write-up, please write to Sherry (email link at bottom of this page). I will get an email address for you to facilitate the process. Thank you.]