Greenwell Farms and Kona coffee farmers struggle to keep their reputation for quality, calling on 

machines for help

By Bronson Doria

Robots vs. Bugs

When bugs get tough, people get tools

Coffee beans shoot out of a mechanical opening, with most of them falling into a bag fastened to the bottom of the machine. However, some are shot away by a burst of air throwing them out of the cycle. Those beans, the machine has determined, are infested with Coffee Beetle Borer or (CBB), a tiny pest that has infested most coffee regions across the globe, including Hawaii.


With worsening problems with the bugs and technological innovations emerging in a fast-changing environment, Tommy Greenwell, a fourth generation coffee farmer, has reinforced his Kona coffee farm with new mechanical and technological agricultural equipment. In such ways, the Kona Coffee industry continues to painstakingly protect their product’s quality and yield from miniscule pests. They also are dealing with a shrinking number of available laborers. In turn, Greenwell has begun looking into the prospects of automatic, or robotic, harvesting in an industry built upon hand-picked, quality coffee.

“(Controlling CBB has) added a lot to our expenses, and we also have a labor shortage," said Suzanne Shriner, the president of the Kona Coffee Farmers Association. "So finding people to strip the trees can be even more expensive, generally in the range of $15 to $20.”


As the numbers of labor for coffee farming in Kona has been dwindling, the same can be seen across the nation in agriculture regardless of the crop. So in recent years, there has been more of an industry-wide push for automated farm equipment. New technological advancements, such as computer eyes or lenses, have increased the accuracy and speeds for equipment used to seed or harvest crops, like with coffee.

According to a case study on the Hawaii Macadamia Nut Company, even Hawaii’s macadamia nut industry has moved toward mechanical or automated machines, which has been more efficient than handpicking the nuts off the ground. Around 35 percent of its annual production is collected by hand. Two student teams in 2016 and 2017 from the Arizona College of Engineering created and updated a prototype for macadamia nut harvesting in Hawaii.

“It consisted of a vehicle platform with a hopper for carrying harvested nuts, a sweeper arm and pickup head for collecting them, and electrical components for power and navigation,” according to the report on Arizona’s Autonomous Macadamia Nut Harvester Enhancement Project. Greenwell sees developments like that and is encouraged about what is possible.


In Hawaii, there are a small number of coffee farms that mechanically harvest. On Kauai farms, for example, their coffee growers use 12 mechanical harvesters that originally were designed to harvest blueberries and have been modified to be more efficient for picking coffee cherry. The Greenwells in the late 1970s and early ‘80s tried using a mechanical raspberry picker for the same purpose, but the fuel and the extra costs were not feasible, because hand-picking the coffee cherries was much cheaper then and reassured the coffee’s quality. However, more than a decade into the 21st century, the price of coffee workers has jumped up, due to a shortage of labor in Kona. This, along with the expenses for CBB control, are leaving farmers with little or no profit. "The price of Kona Coffee at the market is very high, but a lot of that doesn’t always come back all the way to the farmer, because so much goes into expenses,” Shriner said.


In Greenwell’s warehouse, on his family-owned farm, hydraulic pumps and gears hiss and buzz from a group of machines echoing against its steel walls. The machines are used for bagging and sorting a large amount of coffee. Without this warehouse and the equipment inside, Greenwell would be struggling to provide the quality of coffee that he takes pride in producing. The workers in the warehouse are going through their daily routine, as Greenwell walks in with one of the many local farmers who sells their coffee cherries to Greenwell farms, which is later processed and sold under Greenwell’s brand.

For Kona farmers, taking coffee cherries to processing mills is the less profitable route, but most Kona coffee farmers choose that route out of expediency. Small-acre coffee farmers, or those who have jobs other than their farms, choose this path because it's easier and less labor intensive. These mills or larger farms, like Greenwell's, buy these smaller farm’s coffee cherries per pound, ranging from around $1.20 to $2. “About 75 percent of Kona coffee farmers still sell cherry to wet mills, and when you sell cherry you can get two dollars, (per pound) if you’re lucky,” Shriner said.


As he shows his customer around, Greenwell focuses the farmer’s attention to the warehouse’s electronic bean sorter. This machine in front of them, on a raised platform, constantly filters out beans that have been bored out by the (CBB) pest. This small pest has caused turmoil for many Kona farmers, as these small beetles survive off of ripened coffee cherries. The females bore into the coffee bean, and, if left along long enough, are capable of laying anywhere from 30 to 50 eggs in a single bean in a matter of seven weeks or less.

One of the warehouse workers taking a break is interested in the two farmers' conversation and walks over as they observe the sorting machine. Once the warehouse worker announced his presence, Greenwell quickly assigned the worker to help him sift through some recently processed coffee.


Greenwell grabs a handful of beans that were shot out of the cycle from the sorter and begins picking out beans with tiny holes to show how precise his sorter can pick out and sift through damaged, or any undesired, coffee beans. After finding some beans with holes the width of a sesame seed or a pinhole, Greenwell raises the coffee bean to some light and the visiting farmer leans in.



“Yeah, on that bean,” Greenwell lifts and drops the bean, as it drops to the wooden platform, “dropping that fast, it’s crazy. Crazy.”

Both farmers continue to admire the machine. As the farmers decide to move on, so does their conversation, which switches to the new and persisting hassles and changing environment that is forcing Kona coffee farmers to adapt. The Kona coffee industry has been forced to change their farming methods, even leading some farmers to quit the industry.

Graph by: Bronson Doria

Graph by: Bronson Doria

Coffee farmers trying new tricks

Many of the smaller Kona coffee farms choose to sell their coffee to processing mills or other farmers willing to buy cherry, and Greenwell Farms is one of the two major wet mills operating for the majority of Kona’s coffee production.

With a heavier workload and pest control costs stacking up, some small farms just are opting out of the coffee business. But there is also a growing group within the industry appealing to the private market directly. Some Kona farmers say that is the only way for small production farmers to see a profit.

“It’s really the only way as a farmer to be financially successful," Shriner said. "It takes 8 pounds of cherry to make 1 pound of roasted coffee, but I can sell my own roasted from $27 to $35 a pound. So if I sell my red cherry, I'm giving all of that profit away to someone else.”

One of these Kona farmers in the growing private Kona market is Francisco Javar, who owns a 4.5-acre farm with roughly 1,400 coffee trees and other crops as well. Javar uses custom roasting and packaging services at Greenwell farms, helping Javar to manage the high costs of pest control.

“I thought even if I get all that, (it) would still be cheaper if I just went to Greenwell," Javar said.

Javar cares and harvests his trees and has a personal wet mill and drying system at his farm. His decision to operate privately has saved him from the growing labor wages seen but not the CBB control expenses. Javar points out that he’s left with few options as workers to help him with the bugs are hard to find.

“Who's going to pick their 150, 175 acres," Javar said of the big farms scooping up all available laborers. "So any farm worker that comes down, all goes to them. All these people who fly in and then out after the season go to the big farmers.”

Working solely on his farm has been enough to keep him financially afloat, he said, primarily because he keeps a small personal customer base. With Kona’s high coffee value, he’s seeing profits in those direct sales, where some of the less-resourceful are left struggling.

Recent economic uncertainty, the labor shortage and rising CBB control costs in Kona all affect the industry, Javar said. Problems in Kona even have caused some of the large mills, such as Mountain Thunder, to go bankrupt, leaving only Greenwell and a few other mills open for purchasing and selling Kona Coffee.

“Mountain Thunder use to do this. They bring in coffee from other countries," Javar said. "The quality is down, and they owe people money, but nothing. No one was getting paid. ... And now what? Bankrupt. So I think only Greenwell is the biggest one now.”

The beetle problem hit south Kona by surprise in 2010-2011. With little to no clues as to what the Coffee Beetle Borer was, the future of Kona Coffee was in danger. By 2012, the production of Kona Coffee suddenly was at high risk of collapse, due to the rapid spread of CBB infestations across the island of Hawaii.  

According to a USDA National Agricultural Statistics Service report, released in September 2012, “Hawaii coffee marketing for 2011-2012 was estimated at 7.6 million pounds, 14 percent less than the 2010/11 season.” It also mentioned yield then, as averaging 1,210 pounds per acre, which was a drop of 190 pounds from the previous season.

The beetle problem continued to spread making it a large and pressing issue for the state in 2014, when the tiny beetle made its way to Oahu. Last year, the pest also was found on Maui.

In the 2014-2015 Kona coffee season, the situation seemed to improve, but in the 2015-2016 coffee season, the CBB pests struck back even worse. The 2015-2016 season began later than usual, as there was a light start of rain to kick off the harvesting season. This slow start to the season was soon to turn into a heavy drought that year.

By the middle of the harvesting season, in August-September, coffee trees around Kona began to wither, and farmers without irrigations systems suffered. Blooming flowers on the coffee trees were falling, potentially shortening the season’s production yield, as the surviving flowers would later turn into cherries.

The harsh weather also delayed the startup of the CBB pest infestations. Since cherries were slow to ripen, so was the CBB beetle’s desire to bore through a red cherry. The drought was bad, leaving many farmers struggling to keep their trees healthy for that year’s season. The island of Hawaii’s water supplies were low, and with Kona’s rocky and rough terrain, it can be hard – and expensive – to irrigate a thousand or more coffee trees.

The 2015-2016 season was tough even for Greenwell, he said, who at one point resorted to pulling out his garden hose after hours in an attempt to cool down his trees. Usually Kona experiences cool mornings with afternoon showers, which benefit coffee production. However, with the continuing dry spell, Greenwell noticed his trees were hurting. His tree’s leaves were turning brown and withering up while the branches were drooping down. “Definitely not a good sign,” he said.

So in the late afternoons, Greenwell would crack open some beers, while watering down what trees he could.

“I’d be there with one of my Budweisers, watching the sun set, with my water hose in the other hand,” Greenwell said. “That drought was tough. I mean we were trying whatever we could to keep the trees healthy.”

That year’s drought coupled with the growing labor shortage cut into Kona’s production yield, leaving more than 1 million pounds of coffee abandoned statewide, meaning it never reached the market. The USDA’s National Agricultural Statistics Service put that number at 1.8 million pounds of cherry harvested but not sold for the 2015-2016 season, including coffee farms on Kauai, Maui and Oahu. 

During that drought in 2015, initiatives were being implemented and already in use. The University of Hawaii College for Tropical Agriculture and Human Resources, along with other agricultural pest specialists from Latin America, where CBB has been inflicting their coffee since the 1980s, joined local farmers, who were applying for grants to help farmers control costs. They also were opening free workshops to help educate farmers on how to control and prevent larger CBB infestations.

The state’s subsidy program was in effect as well. It assists farmers with an effective entomopathogenic fungus, Beauveria bassiana, used through a spray. 
Beauveria bassiana naturally infects CBB in countries including Brazil and other Latin countries. The fungus has been developed as an environmentally safe bioinsecticide used against CBB but is not toxic to workers and has low impact on non-target organisms. According to a 2016 study in the academic journal Insects,“The effectiveness of B. bassiana under field conditions depends on several factors, including the strain, concentration, virulence, weather conditions, and application efficiency.”

Even with coffee at a high demand, and prices in a good position, costs to control CBB stacked up, especially when the efficiency of the Botanic-Guard or Beauveria bassiana depends on the Kona weather, the time of spraying during the season and how often the fungus gets sprayed onto trees. Around this time, the same mills began refusing cherries over a certain percentage of infestation. Some mills sent out letters to Kona Coffee growers stating that rejections of red cherries would start at about 40 percent damage. That was not a hard threshold to reach.

Comparing the beetle size to the coffee berry.

Graphic by: Bronson Doria

Usually, the Kona coffee season alternates, in a predictable trend: one year has a good amount of rain and leaves farmers with a heavy, concentrated production, and the 2016 to 2017 season, saw a good amount of rain, leaving Kona farmers with a larger yield. However, a larger production yield also has its own issues as well. With Kona’s labor shortages still leaving farmers short of hands, many of the red cherries quickly ripened or were taken over by infestation, because they were left on the trees too long, becoming useless but also spreading the pests.

Greenwell managed to control his coffee infestation and to buy the local farmers coffee that was sold to his mill, while also paying about 50 employees to harvest, clean and process his coffee. But he was one of the fortunate ones.

“It used to be a ratio of five to one, five pounds of coffee to one pound of sellable grade A coffee," he said. "Today we’re talking seven to one, which also doubles the price.”

The high value of Kona coffee has been saving most Kona farmers from giving up, and the price of Hawaii’s coffee seems to be holding in that high range. Red cherry price per pound increased from $1.71 to $1.79, which Greenwell and Shriner say are true to Kona’s market. But it still is one of the highest price ranges seen in Kona’s history. Can it last?

Last year’s season estimated a loss of more than 700 pounds per acre, and that’s around $1,400 out of pocket for farmers. For private farmers or those selling on the green bean market last season, they were averaging statewide around $14.30 per pound.

The CBB infestation in Kona for the 2015-2016 season ranged from 1 to 35 percent for local coffee farmers.

According to the USDA NASS report on coffee released this January, the production last season for utilized coffee dropped 15 percent for the state. Yet, the drop in prices were still high when compared to the season before that, which gave sellers $16.50 per pound, and the season before that in 2015, when sellers were seeing $10.50 per pound.

“Coffee is at a good price, but no one’s seeing it in their pocket book because it's all going to control,” Greenwell said. “I gotta buy the coffee, because we gotta keep the farmers in business.” 

Over the years, while fighting to control his farm's CBB infestation, Greenwell had to invest more money into equipment, while also paying more for labor as well. As demand rises, prices goes up, he said, meaning higher profits for Kona coffee farmers. But for Greenwell, that also meant buying coffee from 300 to 400 coffee farmers at a higher price.

Tommy Greenwell, talking about his Kona coffee farm.

Video by: Bronson Doria

Coffee farmers today have to look forward

Greenwell has been fighting for his family's coffee business ever since his father passed down the responsibility.


“We’ve been farming for 150 something years," he said, "and now, all of a sudden, we have to change our farming habits.”

Greenwell’s great-grandfather sailed to Austria in the 1800s and won a Kaiser’s medal for best product in the World’s Fair. Later, Greenwell’s father ran the family farm. Now, it Greenwell's turn to keep up the family legacy.

He usually start his day with his morning cup of Kona coffee,


“It only takes a few beans with CBB to ruin a cup," he said. "I like the taste of my coffee; that’s why I drink it black. I can taste the quality of the coffee.”

On this particular day, just an ordinary day, he contemplates the many tasks ahead and reaches out for his white mug of coffee, with a Greenwell Farms logo printed on the side, and gulps the rest down, finishing his cup.

Greenwell goes back to the three drip coffee brewers he keeps fully stocked in the office, for a refill. As the steam from the coffee maker releases into the air, and his medium roast pours into his mug – surrounded by the aroma and enticing scents of roasted coffee – Greenwell says he can even taste it when the beetle kills the Kona coffee quality.

“You know how this doesn’t have any beetles in it," he said.  "You know the best way to tell is: If you drink black coffee, and it starts getting cold, if the coffee is bitter, like there’s a metallic taste. Then that coffee has some percentage of infestation.”

The visiting farmer and Greenwell sat in the meeting room in the main office, which is filled with rusty antiques, and heirlooms and antique family photos from the old days of coffee growing in Hawaii. Across the room, a photo hangs showing Greenwell with his late father, who helped to pioneer the family business. In the photo, the two Greenwells pose on a large mechanical harvester, both grinning, dressed in stained blue jeans and snapback caps tightly fitted on their heads.

Separation from the times in that hanging photo grows every day as problems with harvesting coffee worsens.

Not long after returning from seeing all the equipment, Greenwell brings up one of his concepts for the future of coffee farming.


“I tried to get UH interested, I have a good concept for robotic harvesting,” Greenwell said. Even though automated or robotic harvesting seems suitable to cover Greenwell’s various coffee expenses, the technology or mechanics for harvesting coffee has not met the needs for Kona’s terrain or the precise needs to keep Kona’s high quality coffee. Many Kona farmers believe that with harvesting technology now, using it on Kona coffee farms would only deter Kona’s reputation for quality.

“Kona coffee is a very high value crop," Shriner said, "and one of the reasons we get that high dollar for it is because we hand pick our red cherries, and those have the most flavor and are low in defect." 

Shriner added that most farmers have small acreage farms, and most of the terrain for Kona Coffee is rough and rocky, which is not very suitable for such equipment.

Greenwell is heading for the door, leaving the farm’s main office. The day is just starting, as the sun creeps over the sloping west side of Mauna Loa. The sun breaks through the field of coffee trees, creating a reflection on the leaves causing them to shimmer.

A growing number of Kona coffee farmers have been receiving $1.85 per pound of cherry this year, if their cherries have no more than 10 percent CBB infestation. Although some mention that a 10 percent average is in the right realm, it’s still higher than infestations seen by competitors in Latin American countries who have been dealing with CBB much longer than Hawaii has.


Greenwell says spraying and other post-harvest CBB control only account for 25 to 30 percent of the efforts. A majority of the control process includes hand labor, scanning and cleaning the coffee trees and grounds, meaning stripping the trees of dead beans and clearing dead branches or leaves from the ground.

“I’m constantly walking by the trees, and I’m looking at beans, picking them," he said. "It just becomes a habit, like where I can just spot it from afar, where it’s like 8 feet away, and I can tell. You know there’s a CBB, or a berry that’s been attacked by a CBB.”



Written By: Bronson Doria

Published: May 14, 2018