Controlled Environment Growing
9.4 Indoor Production
Moving production into an insulated building is suitable for producers who want to be close to urban markets, have a lack of arable land, or live in a climate not suitable for outdoor or greenhouse production. No matter where a plant is grown, it still requires optimal conditions to reach its maximum yield potential. In addition to the controls discussed above, producers must also provide light suitable for optimal plant growth.
· Kentucky State University9.3 Heating and Cooling Options
Heating: For small or backyard-size producers, implementing a passive heating system can help reduce heating costs during cold months. In this type of system, sunlight enters the south wall. The north wall has reflective material to trap and store heat. Black barrels filled with water absorb heat from sunlight during the day and slowly release the heat during the night. Thermal curtains can be hung on the south wall to trap heat during the night (Figure 26).
· Kentucky State University9.2 Greenhouse Covering Options
Greenhouse coverings come in a variety of materials, including glass, rigid plastic (fiberglass, polycarbonate, or acrylic), and plastic films. The appropriate choice depends on your climate zone and budget. Regions with a colder climate will require the covering to provide increased insulation and low heat transfer measured by the R-value and U-value, respectively. The R-value measures how well the material insulates. The higher the R-value, the more insulation the material provides.
· Kentucky State University9.1 Types of Greenhouses
Free-standing greenhouses come in a variety of shapes and sizes (Figure 24). Choice of greenhouse depends on snow load and wind speed of a particular location. Free-standing greenhouses are less expensive than larger structures and are easier to optimize environmental parameters for different crop species. If multiple stand-alone structures are used, increased sanitation protocols are required to prevent insect pest and disease issues from being transferred between structures by workers.
· Kentucky State University