High Tunnels


Growing crops in greenhouses is fast becoming a preferred norm in the agricultural community- Cultivation of Cannabis in a Green- house is also proven the way to go and is preferably for farmers and even many of the law enforcement officials across the country and in Northern California as well. As the these structures are lockable and can be controlled to eliminate odors. These greenhouses are called High Tunnels which are actually a high tech "cold frames" and not the traditional wood & glass greenhouse as they are considered "temporary structures" which can greatly aid agriculture operations. The USDA now encourages and even funds High Tunnels for farmers growing conventional crops as these systems conserve water, power, and serve as a habitat for biological alternatives for pest control (such as ladybugs and lacewings) instead of chemical pesticides. These High Tunnel systems may utilize natural ventilation and passive solar principals to enhance production and do not rely on electricity or heating fuels. Although more and more growers are using High Tech Hybrid technology that merges advanced digital electronic systems AND natural elements to produce High Quality Crops. Both High Tech and Low Tech Greenhouses (High Tunnels) allow cultivators to limit production costs and benefit the environment by cutting down the carbon footprint of growing operations. Because of this, greenhouses have taken hold in both the conventional crop and cannabis industry. As cultivation expert Jorge Cervantes put it, "...a greenhouse is one of the best places to grow medicinal marijuana." Cannabis growers see the same advantages of being able to control the environmental conditions of their plants as well as having an alternative to chemical farming- add to this the added necessity of physical security and biological isolation and these systems are the wave of the future in crop production. Across the country more and more square footage is utilized for growing non-psychoactive cannabis for medicine (High CBD) varieties and more recently, for recreational (THC) use, where it is allowed. Medicinal growers find with a greenhouse, they can eliminate cross pollination isolate the mostly CBD strains that have been medically proven to alleviate pain, nausea, seizures; spasticity, epilepsy and neuropathic pain. It seems likely that it is just a matter of time before limited personal grows of THC types in a secure structure as well as large-scale commercial (and TAXABLE) grows of the CBD types will be allowed. Being able to lock the doors and keep those who should not have access to cannabis (primarily children and pets) is another reason for growing in a greenhouse, as these structures can be hardened to control access. Several nearby county officials have expressed to their growing communities that they would prefer all grows be indoor (greenhouse) and even some counties with the most restrictive 'rules' still license secure greenhouse grows. While most greenhouse grows are in rural areas an on agricultural land, greenhouses are also suitable for urban settings- as they can be seen as compliant- if the grower can assure authorities that the structure can be secured have virtually little negative footprint You can also control the smell by using carbon exhaust filters and utilizing light proof covers to eliminate light pollution. Where it is currently allowed (or not)- more and more people are growing pot. Personal use is the main reason with commercial production close behind- with CBD varieties grown for commercial medicinal use showing great signs of promise. Bottom line is that virtually all the growers I meet tell me that just really enjoy growing the herb.


That you can depend on!

for Forced-Flowering Control

For High Tunnels, Greenhouses & Hoop Houses

and Personel and Medicinal Cannabis Growing Systems




DISCLAIMER - These systems are intended for legal purposes only under all applicable local, state, federal laws and ordinances. Grizzly Hill and our vendors do not encourage or otherwise advocate the illegal use, cultivation, manfacture, distribution or sales of illicit plants or controlled substances in any way.

Complete AUTOMATIC Light Depo System NOW-- $1900 Complete!


GROUND MOUNT; (tarp extra)


Youtube Video.


View our OVER-THE-TOP Depo Video

The Systems Listed here are: KEEP IT SIMPLE- Our Basic AUTO System - Timer / Power Supply – This system consists of an AUTO or Manual Switching and Reset controls, an Intermatic Timer and a Waterproof 24 volt Power Supply- This Controller runs on 120 vac and controls the 24 vdc Dep Motors allowing for different opening & closing times - We also offer: An All SOLAR Version of the model shown below... that works with a 24 vdc Power Supply- from a Solar System.

COMPLETE AUTOMATION- The modified iGROW Greenhouse Controllers are a more technical system that can control not only the Light but all aspects of your growing system- The Modified IGROW system with an onboard power supply and 6 or MORE channels for control of other functions of your Greenhouse. Whether you choose a simple or more comprehensive Auto Light Deprivation System- these are upgradable and can be modified to accept new technology – FOR A FULL REVIEW OFTHE IGROW SYSTEMEM- CONTACT US!


This system is engineered to ensure a smooth & easy operation of our Telescoping Tubes and other quality Components for our Telescoping Tubes utilizing Teflon Slides and Self-Retracting Cable

Our Motors are top-quality 24 vdc, High-Torque (100 Nm), Waterproof, with Built-in Limit Switches and easy to adjust controls-


Over-The Top System Drawing

See our Current Projects HERE!

We provide Complete High Quality Kits for building both Cold Frames, High Tunnels and Commercial Greenhouses. These Kits are complete and include the Precision Bent Frames, State-of-the-Art Hardware & Software and a selection Greenhouse Coverings. They are easy to construct and offer an affordable Solution to Extending your Crop Production.

iGrow will also let you know how much energy your greenhouse is using- allowing you to adjust- to save money- You can also see which equipment is using the most energy...





OUR AUTO DEPO SYSTEM offers the capability of shortening your photoperiod to force blooming and bring your garden to harvest on a controlled schedule - using your own or a shared schedule that allows you to document your growing parameters and share with others- You can modify your schedule for different genetic strains and other conditions.


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A LIGHT DEPRIVATION SYSTEM modifies the Photoperiod for Plants by controlling the amount of Light entering the Greenhouse and the length of these alternating Light /Dark Periods- This function is usually a Timed-Auto function or a manually controlled Systems range from simple Mechanical Tarping System to a Completely Automated Auto -Darkening Photoperiod Control Systems for Greenhouse Crops.

Daylength exerts profound effects on the growth and flowering of many plant species, and manipulation of daylength is essential for scheduling several greenhouse crops. The responses of plants to daylength may appear to be a perplexing subject, but it is easy to understand once some basic concepts are mastered. This article briefly reviews photoperiodism and photoperiod control systems for greenhouses. Photoperiod control is necessary for scheduling greenhouse crops such as mum, kalanchoe, Holiday cactus, and poinsettia. The latitude and species will determine whether shortening or lengthening of the daylength is needed. There are two types of photoperiod control systems used in commercial greenhouses: (1) using incandescent, fluorescent, or high-intensity discharge (HID) lamps during naturally short days (SD) to create artificial long days (LD); and (2) using opaque black cloth (or similar material) during naturally LD in order to create artificial SD.
Shortening the daylength (artificial SD). Plants are covered with an opaque material that reduces the light intensity. To be effective, the light intensity must be decreased to less than 2 ft-c under the material. In most operations, plants are covered at 4-5 pm and shade is removed at 7-8 am to provide an 8-hour day. A 4’ height is recommended between the top of cloth and the bench (bed) top to reduce heat buildup around plants; tall crops (such as cut mums) require more height. The material must be placed over the plants continuously (every evening) until the response is maximal. Several types of materials can be used to cover plants, and include the following: (1) black sateen cloth is a jet black woven cloth made from cotton or a cotton/polyester blend, and costs Vary (Call us) per square yard; (2) polyolefin sheeting is a woven material that is tear-resistant and waterproof, and costs ¯(Call US) 0 per square yard; and (3) 4-6 mil black/white plastic can be used but is not tear-resistant, and costs $0.27-0.41* per square yard. Tears and worn spots should be repaired, and overlaps of shading materials should be properly sealed to minimize light leakage. Occasional 24-hour skips in shading are not catastrophic, but flowering can be delayed. For mums, every day that shading is skipped delays flowering by one additional day. Failure to shade consistently may also cause irregular opening of flowers.