When it was Mississippi’s turn to legalize hemp cultivation in 2020, some growers’ first year of production did not come without some major challenges. “After they passed the legislation, I was excited to be able to legally start a commercial production,” says Bobby Mitchell, owner of Bunker Hill Hemp Farm. “Unfortunately, we learned that the hot and humid climate did not combine well with the greenhouse production. With powdery mildew and mold being the result, we ended up having to pull the plug on everything. While this was an expensive experiment for us, there were lessons learned that can be beneficial for other hemp growers in the state.”
Burning the greenhouse-grown hemp plants
A great start
While the experiment did not end positively, it did not start on a bad note at all. “I was excited to finally start and purchased 13 acres of land as soon as they passed the legislation. I built a greenhouse and got all the facilities set up to grow the hemp. We started growing in the spring of 2021, with the goal of selling it locally through retail locations. We grew about 300 plants in the greenhouse. Because we were unsure of what varieties would work well in the Mississippi climate, we used 6 different strains. The genetics we could purchase were from the more northern climate, where it is much dryer than in our state. Still, we were hoping that with the right measures, we could make this work for us.”
Mitchell explains that they had two 60-inch fans circulating the air through the greenhouse on top of eight oscillating fans and keeping the greenhouse open to maximize the air flow. “During the spring, the plants were thriving, looking full, green, and healthy.”
A turn for the worse
But then summer came around, and that is where the problems started, explains Mitchell. “Our heat index in Mississippi can get well into the 100 degrees Fahrenheit in the summer. I had difficulty keeping the heat down in the greenhouse, as we were getting temperatures of 90 degrees consistently. As we knew the plants would not enjoy this consistent heat, we tried to keep them watered appropriately to manage evaporation. What we didn’t plan for was that the heat and humidity were so high that the moisture was accumulating inside the greenhouse. Instead of the fans exchanging the moisture out, we were pulling in high humidity air and pushing it through the greenhouse.”
With the temperature dropping around 20 degrees during the nighttime, moisture would accumulate on the canopy of the greenhouse. “With that moisture then dropping on the plants, they would basically get rained on during the night without enough drying time during the day. That is when we started to notice the powdery mildew and a little mold.”
Trying to find a solution
With their production, the farm wanted to be as organic as possible, using organic fertilizers and soil. “We researched organic solutions to combat the mildew and mold and consulted with other growers. Whatever concoctions we tried, we just could not keep up with the spread of the diseases. We did notice that the Sativa strain lasted the longest, until late August/early September. This was probably the case because the plants were so tall and the buds less dense, meaning that they were very airy. The Indica and Hybrids did not make it through the humidity as long. Using pesticides or herbicides was not an option for us, and with no way to market any plants that would be considered lower quality, we decided to pull the plug on the greenhouse.”
Lessons learned
Of course, Mitchell is not the only hemp grower in the state, and others will recognize his challenges. “There were 300 registered growers in Mississippi last year. Other growers I have talked to have had very similar problems as me. Luckily, my experiment can provide current and aspiring growers with some useful information. First of all, for outdoor production and greenhouses, I would recommend using autoflowers. With their very short growing period, the production would be complete before the summer heat hits. Moreover, our experience taught us that growing in a greenhouse may not be the best solution. The greenhouse simply attracts too much heat and moisture in the summer.”
Luckily, all hope is definitely not lost for Mitchell’s company. “We are now starting a medical cannabis production, as we believe this will be much more successful and profitable for us. Our indoor flowers grown last year did really well. Therefore, with some lessons learned these past years, we are very excited about the future opportunities for us.”
Moreover, while being busy with his trial hemp production, Mitchell was using his spare time to invent a patent-pending trellising system. “As a small company, we were losing time and resources when harvesting our crops with the normal synthetic trellising netting. If we don’t have enough help on site, the process is difficult, and everything can become a tangled mess with the danger of damaging the plants. I designed a way to make the process easier for growers. That is when I created and built a prototype of a retractable and permanent trellis system, the Green Tree Scrog. “It’s fast and easy to set up, effortless to remove from your plants, and designed to last a lifetime with very low maintenance and zero waste. We are currently testing it and comparing the side-by-side data against traditional synthetic trellising methods. With the excitement I have already experienced from local growers, I don’t see anyone going back to the old ways.”
For more information:
Bobby Mitchell
LinkedIn
www.gtscrog.com
www.bunkerhillhemp.com