Whether starting vegetables and ornamentals for transplant or raising crops year-round, a greenhouse is a handy facility for gardeners. Using less soil – or using soil less frequently – helps to maintain its health and organic vitality. In addition, indoor gardening is less vulnerable to the sudden unpredictability of weather and climate.
Plant enthusiasts have so many more options with a permanent shelter for indoor growing. Yet enthusiasm should not hinder clear thinking. The size and style of conservatory should fit the plants that grow, the aims of the grower and the available budget. Knowing these helps you in how to build a greenhouse.
1. Scout a Location
How to build a greenhouse starts with where to place one. Maximum sunlight should be top priority. If compromises must occur, err on the side of morning light, i.e. on the eastern side of the property. If deciduous trees like oak or maple sit to the west, they will shade the plants from the raging sun of summer afternoons. In winter, they are bare and the sunlight is more benign. Evergreen trees do not provide this benefit so if you can avoid them…
2. Determine Size and Usage
Doubtless you have seen all kinds of greenhouses ranging from little window extensions to the gargantuan U.S. Botanical Garden in Washington, D.C. If your budget is limited, a lean-to might be what you are looking for. These greenhouses simply extend from a building or house, thereby partaking of a common wall. This saves on materials.
A freestanding greenhouse, on the other hand, has the advantage of sunlight on all sides, and sport A-Frame and quonset designs (among others). These enclosures can be functional or decorative…or both. Furthermore, you can opt to keep them as simple shelters with dirt floors or full-scale incubators with their own heat and irrigation.
3. Construct a Frame
When learning how to build a greenhouse, never neglect the importance of quality materials when building the frame. This is the very skeleton of your conservatory and must be structurally sound. Frames of wood, steel, and aluminum are generally reliable plastic, or PVC, components to not stand up well to snow and ice so use them only in a southern or tropical region.
Equally important are the brackets, bolts and nuts that hold the frame together. These fasteners will have to weather the elements in both cold and warm climes. Wood screws are used at ridges and closures; machine bolts at vents and sashes; and roundhead screws in the rafters. These examples demonstrate the specificity with which you must procure the hardware. Lengths and diameters should correspond to the frame pieces.
4. Select and Install the Covering
Were it not for the covering panels, a greenhouse would just be a shed. In fact, the covering – or glazing – is essentially the most crucial and operative element. The student of how to build a greenhouse must major in glazing. This is because covering has a two-fold purpose: protect the plants from the weather and serve as a conduit for sunlight.
Polyethylene film is both inexpensive and widely popular among gardeners. Though costlier, glass panels are better looking and is more defiant against ultraviolet radiation. Rigid plastics like fiberglass are more durable and transmit light very effectively. Meanwhile, double-layered acrylic or polycarbonate help to retain heat, but also allow less light to penetrate.
5. Determine Optimal Temperature and Circulation
Different plants thrive under varying conditions. A prudent gardener seeks to provide the right heating, cooling and ventilation for the flora in the greenhouse. Those asking how to build a greenhouse must also ask how the conservatory will protect their plants’ health. Just as you would not want frigid air to kill your vegetables, neither do you want them overheating.
Cooling systems include mechanical devices, natural ventilation and the use of shade. Many professional greenhouse managers utilize shade cloth or curtains to cover the panels. Although this proves to lower the temperature by 10 degrees F, it can also obstruct needed light. The key here is balance.
Evaporative cooling walls can help to reduce humidity while vents in the walls and roof will release excess heat. Circulation fans are always good to have on hand. A ground-to-air heat exchanger or a portable space heater are ordinarily sufficient to keep plants warm in the cold of winter.
6. Install Irrigation Systems
No instruction in how to build a greenhouse is complete without looking at irrigation. If your conservatory is small, the task of watering is easily performed with pitcher or spray bottle. Larger greenhouses, however, more frequently emply more sophisticated techniques. Growing vegetables in bags, pots mor beds lends itself well to drip systems. Here the volume of water is subject to control, as is the timing of application.
For the more environmentally zealous, sub-irrigation is a way to conserve the runoff of water and fertilizer. Under this regime, water and nutrients are preserved underneath the container, fising through perforations, the medium and root systems by capillary action. This means that the H2O molecules move upward by attraction to the porous surface of the container.
If you learn how to build a greenhouse, you should likewise know how to maintain one. The health of your plants depends on a clean and functional indoor environment. Removing weeds and scrubbing the inevitable algae from surfaces is an advisable springtime (or any time) chore. Cleaning the glazing at regular intervals also benefits your crops. It also helps to test your heating system after the summer and the irrigation system after the winter.
Building a greenhouse has so many variables that the decisions you make on location, style, materials, ventilation and operating systems will determine the steps for putting the conservatory together. The advantageous thing about most greenhouse designs is that they are flexible. You can always start small and add on. Most important is what you grow. Once the needs of the plants are evident, the steps to build will then fall into place.