I met a cannabis cultivator at a cannabis and health conference in Oahu, Hawaii this past January. He invited me to visit his farm located on the North shore of Oahu. He serves about 100 patients, with each patient being allowed 10 plants (Jason Care Facility grows about 1,000 plants). It’s all done within a 40 x 60 foot structure, a total of 2,400 square feet. The side walls are 10 feet high and the peak reaches 17 feet.
The main purpose of the greenhouse is to protect plants from rain and wind. The temperature range on the island of Oahu is considered mild, so the major problems are rain and moisture. The lowest temperature occurs in January when the thermometer dips into the high 60s, but most of the time it ranges between the 70s and low 80s and the temperature rises no higher than the high 80s during the summer months of June, July and August.
To prevent the greenhouse effect, when heat generated by sunlight heats up a closed area, the sides of the greenhouse are lifted up during the day for airflow. They are closed at night and on rainy and windy days.
Oahu is located at the 21st parallel north, a circle of latitude, and there is only slight variation between summer and winter day length. On June 22, the longest day, there are just under 13.5 hours of light. On the shortest day, Dec. 21, there are just under 11 hours. As a result, almost all plants start to flower soon after germination unless the length of the light period is extended.
Lighting the plants to prevent flowering is accomplished using compact fluorescent lightbulbs that are hung over the plants. They are controlled using a timer that turns the lights on most of the night.
Since it is so easy to manipulate the flowering cycle, there are plants in all stages of growth creating a continuous supply and continuous workflow without requiring “bulges” of temporary workers.
The farm manager mentioned that the week around the full moon has a slight effect on flowering, which holds the plants back a bit. I didn’t think that was the case until I looked at the full moon that night. The moon, rather than being at an acute angle in the sky, is much closer to being straight overhead. It is much brighter than it is in the 37th parallel north, where I usually view it.
This farm is trying out many varieties, and is especially impressed with Chem Dog x Durban Poison, Greenpoint Seeds’ Indiana Bubblegum x Stardog and its house strain Blue Dream x Gogi OG. Patients request those varieties the most.
TIP OF THE MONTH
Now is the time to take clones of your favorite plants for sowing outside in a month or two. Give the clones only 18 hours of light per day with a six-hour dark period so they don’t go into shock and immediately start to flower when placed outdoors. Give the clones moderate light until they start developing roots, about 10-15 days. Then transplant them into bigger containers.