A Guide to Light Deprivation Greenhouse Growing
An improved annual yield, greater sustainability, multiple harvests with year-long growing, and a lower production cost… Any one of these advantages would provide a sound reason to make the switch from indoor warehouse grow operations to growing in a greenhouse!
While most strongly associated with the cannabis industry, greenhouses equipped with light deprivation systems can provide a huge out-of-season boon for different types of crops that require specific lighting schedules.
WHAT IS LIGHT DEPRIVATION?
Light deprivation, also called “light depo” or “light dep,” is an agricultural growing technique that controls how often and how much light plants receive.
Light deprivation greenhouses accomplish this by using blackout material to enclose the plants, simulating different seasonal changes. The resulting darkness tricks plants into responding by flowering on command; this allows licensed cannabis growers to reduce the time necessary for plants to reach maturity, and enjoy multiple harvests per year vs. outdoor grows that are entirely limited to a single growing season.
Just as different kinds of plants require different growing conditions, determining the best cannabis plants to grow using light deprivation greenhouses comes down to understanding photoperiodism.
PHOTOPERIODISM AND LIGHT DEPRIVATION SCHEDULES
Photoperiodism is the response from plants and animals, by growth or behavior, to photoperiods.
A photoperiod is the interval within a 24-hour day during which plants or animals are exposed to light.
Crops that bloom in the fall are stimulated to do so by the shorter days and longer nights. While you can delve far more in depth to understand the science behind flowering and how plants mature, for the intentions of this article, you have the information to get started.
THE BEST PLANTS FOR LIGHT DEPRIVATION GREENHOUSES
While certainly open to debate, plants that typically bloom in the fall are known best for light deprivation greenhouse growing. Some of the best plants for this type of growing include:
- Christmas Cactus
Naturally, many of these plants and their individual species and strains can only be harvested in the fall. With a greenhouse equipped with a light deprivation system, however, you can harvest all of the summer cosmos, spring poinsettias, and cannabis you like.
TYPES OF LIGHT DEPRIVATION SETUPS
LIGHT DEPRIVATION HOOP HOUSES (LOW-COST)
The cheapest light deprivation greenhouses involve regularly covering and uncovering a hoop house with a black tarp.
Rebar, wooden planks, and PVC piping are used to make these types of light dep greenhouses. The rebar anchors the PVC that is used to build the frame over the desired garden space. The wooden planks are then used to stabilize the PVC being connected to the pipes across the length of the structure.
Light is controlled by draping a black tarp over the top of the hoop house and manually removing it at the appropriate hour every day.
While this is the least expensive light deprivation option, it requires the most manual labor, and a single mistake in timing can ruin your crops. Do-It-Yourself (DIY) hoop houses don’t usually last more than a single growing season without needing extensive repairs or at the very least replacing the plastic cover and black tarps frequently – as they will degrade quickly when subjected to prolonged UV exposure.
DIY hoop houses are not engineered structures. If you choose to go the cheap route and build a hoop house, be forewarned and understand that should the weather change quickly, your hoop house will either need to be taken down or will likely end up in pieces.
ENTRY-LEVEL GREENHOUSES (MID-RANGE)
Mid-range greenhouse growing can range from backyard greenhouse kits to full-sized commercial greenhouses. The main differentiating factor between this and lower-cost DIY hoop houses is the quality of materials.
Stepping into greenhouses for commercial growing, a mid-range greenhouse with light deprivation can be as small as 20’ wide x 20’ long to as large as 30’ wide to 120’ long. Mid-range greenhouses are usually mass-produced and cheaply made overseas.
These are the greenhouse systems you see on big box store shelves. Instructions for mid-range greenhouses are vague at best, resulting in hours or days of frustrating setup. Like DIY hoop houses, mid-range or entry-level greenhouses can be equipped with light deprivation tarps or blackout material that requires manually opening and closing.
While some of the “better” entry-level greenhouses will have a rating for wind or snow loads, know that these are not actually engineered greenhouse structures designed to meet specific wind or snow loads, but rather general recommendations not to use your greenhouse kit in certain conditions. Failure to heed the warnings could result in your greenhouse and entire crop being destroyed during a storm event.
ENGINEERED GREENHOUSES WITH AUTOMATED LIGHT DEPRIVATION SYSTEMS (HIGH-END)
The highest-quality light deprivation greenhouses are engineered structures designed to meet specific wind and snow loads as well as local and international building codes for safety and durability. Manufactures of such systems have invested the time and resources to create commercial greenhouse systems capable of withstanding the harshest weather conditions for year-round use.
Light deprivation systems and other variables such as humidity, temperature control, air exchange, and even oxygen level for engineered greenhouse buildings are often automated, allowing growers to automate and manage growing conditions.
With automated light deprivation systems, growers no longer need to waste any energy or time on manually opening and closing heavy blackout tarps. You can program all light dep operations ahead of time, and the greenhouse will automatically cover and uncover your plants on the schedule that you provide. This makes your entire greenhouse a much more self-sufficient operation.
Of course, the higher quality and automation come with a higher price tag.
Whereas DIY hoop houses can be built for less than $100 (depending on the size and quality of materials), and mid-range greenhouse kits sell in the range of $100 to $500, engineered greenhouse structures that are automated and custom-designed to meet the specific needs of cannabis growers can range from thousands to hundreds of thousands of dollars.
Understanding the differences in quality as well as the cost for cannabis greenhouses is beneficial for first-time cannabis growers, as well as seasoned growers considering moving from expensive warehouse space used for indoor growing to growing cannabis in a greenhouse!
LIGHT DEPRIVATION GREENHOUSES FROM WEATHERPORT
While many manufacturers sell greenhouses with automated light deprivation systems, none are as well known in the cannabis industry as the GrowPort™ series of greenhouses for growing cannabis from WeatherPort ® Shelter Systems.
GrowPort™ greenhouses offer licensed cannabis growers ease of use and unmatched durability, and are engineered to meet area-specific wind and snow loads. Rely on 50-plus years of proven excellence, utilizing cutting-edge manufacturing techniques, the latest engineering principles, and the highest-quality materials to create an unrivaled cannabis greenhouse solution. All of our greenhouse solutions are custom-designed, engineered, and manufactured in the United States by hard-working Americans.
Benefits of our light deprivation greenhouses include:
- Rapid extinguishing of exterior light
- Eliminates light leakage
- Highly durable, even in extreme weather
- Hassle-free system
- Maximized useable interior space
- Programmable schedule
Choose from a wide range of greenhouse options, including:
- Grow lights (including high pressure sodium grow lights)
- Automated strip vents that provide natural ventilation
- Metal framing systems designed specifically for hanging grow lights and powerful horizontal air flow (HAF) fans
- Wet walls
- Partitions to separate growing areas
- Blackout intake and exhaust fans
- Inlet shutters with light traps
- Automated light deprivation systems
- Humidity and temperature control systems
- Mobile device access — Gone are the days of having to physically be in the greenhouse to control and operate all the growing systems!
Already have a WeatherPort greenhouse? Our Automated Light Deprivation system can also integrate with any existing cannabis greenhouse or grow tent from WeatherPort, so you can upgrade your light deprivation system without having to purchase a new structure.
Request a quote, or call (970) 399-5909 to discuss your cannabis greenhouse needs with a friendly WeatherPort specialist today! Or if you are in the Delta, Colorado area, stop by for a tour of our fully automated greenhouse system.
Want to learn more about growing commercial cannabis? Check out our Guide to Starting a Commercial Cannabis Grow Operation!Improved annual yields, sustainability, yearlong growing, and lowered production cost are all benefits of light deprivation greenhouses. ]]>