Little Leaf Farms: Born Local, Raised Right (Part 2)

"Born Local. Raised Right."
--The motto of Little Leaf Farms

As I mentioned yesterday, Little Leaf Farms is located in Shirley, a 14 acre-site within the Devens Regional Enterprise Zone. This zone is the former location of the 4,400-acre Fort Devens military base and is now administered and regulated by the Devens Enterprise Commission. Within this zone, you'll now find private residences, schools, open parkland, and numerous businesses. Paul Sellew, the founder of Little Leaf Farms, worked with MassDevelopment to acquire the 14-acre site, investing a significant amount of his own money into this endeavor, indicative of his confidence in this project.

A three-acre facility was constructed, with 1 hectare of growing space within the greenhouse, which is the equivalent of about 2.47 acres. The construction of the facility included numerous aspects intended to conserve energy, be more sustainable, and contribute to the success of this hydroponic operation. For example, the Devens site was specifically chosen so they could use more affordable and sustainable energy, as Devens uses a significant portion of solar energy. In addition, the glass used in the construction of the greenhouse was specially designed to maximize the use of natural sunlight. During the winter, when there will be much less natural light for the greenhouse, they will use LED-powered grow lights, which use 40% less electricity than conventional grow lights.

The greenhouse was constructed with a north-pitched roof so that it could collect rainwater, which is then stored in a 2 million-gallon basin located to the rear of the building. One inch of rain provides them about 75,000 gallons of water and their basin is currently two-thirds full. The rainwater is their primary water source and their goal is not to use any other water, absent any significant drought. Interestingly, despite the scarcity of rain this summer, the farm still acquired more water than they needed for their purposes. Thus, they haven't had the same drought problems which have plagued California this year. None of their water is wasted as it is all used by their leafy greens. Their entire system uses about 90% less water than is needed for traditional field-grown lettuce operations, significant savings of an important and limited resource.    

Before the water from the exterior basin can be used in the greenhouse, it is first disinfected with UV light, using the machinery pictured above. This ensures the water isn't tainted before being used to irrigate the leafy greens.

Once the water has been disinfected, it is then stored in this interior water tank, where it will then be used for irrigation, as well as partly for the temperature regulation system.

Most of the operation of the greenhouse is automated, meaning much less labor is necessary, and they currently only have ten employees. They do need to have one of their two growers present every day of the week. The growers include Pieter Slaman, the Head Grower and a fourth-generation Dutch lettuce grower, and Tanya Merrill, the Assistant Grower, who graduated from Cornell University last year with a horticulture degree.

Watching the entire process is amazing, seeing how smoothly it runs, from seeding to packaging. And it all begins with the pelleted non-GMO seeds, like those pictured above, which are obtained from Holland. The seeds are expensive and Little Leaf purchases a large amount of seeds on a regular basis as they harvest on a regular basis.

This is Juan, the "father" of the greenhouse, as he is responsible for seeding.

The entire process begins with an empty, long white plastic growing tray, referred to as a gutter.

Next, a strip of "horticultural stonewool" (pictured above) is placed into each tray. The stonewool is a fibrous substitute for soil and is actually made from crushed and melted rock basalt, which eventually gets spun into wool. This stonewool is specifically designed to hold water and air, and is also natural and inert, meaning it doesn't provide any nutrition to the plants. Because their seeds are grown in stonewool, and not soil, their leafy greens currently cannot be labeled as organic. Hydroponics and organic certification remains an area of contention. Seeds are then added to the stonewool and the tray is then conveyed on a belt to the greenhouse.

For the first three days of their life, the newly seeded trays, are kept beneath the rest of the trays, gaining the shade they need for germination. Once they have sprouted, then the trays will be automatically moved to the same level as the rest of the plants.

Within the green house, there are 12 production lines, with a total of 2130 gutters. The oldest plants are located the closest to the conveyor belts, and the gutters will move forward each day. In addition, as the plants get larger, the space between the gutters increase so that each plant gets sufficient light as crowding could create too much shade. Each day, 120 gutters, per line, will be harvested and it takes only 25 days from seed to harvesting. As such, each gutter could be seeded and harvested about 14 times during the course of a year. They do not harvest at full maturity, harvesting at a time when they feel the leafy greens are at maximum flavor. Maintaining the balance of the lines and gutters is very important to their operation.

This is a gutter which I witnessed being moved to the conveyor belt, ready to be harvested, and headed to the cutting room.

Paul stated that their projected annual yield should be in the low millions of pounds! Hypothetically, if their total yield were 2,000,000 pounds, that would equate to 1000 tons, or about 400 tons per acre. Now, let's compare that to the average yield of leafy greens on an acre of land in California, which is only 12 tons. Little Leaf is producing as much leafy greens on one acre as it would take for over 33 acres in California. That is incredible and is a massive savings in valuable resources. As I said yesterday, lettuce production occurs on about 323,000 acres, but if the Little Leaf process was used, you could decrease that amount down to only 9700 acres!

Little Leaf uses a hydroponic system known as "nutrient film technique," where, in short, water containing nutrients, feeds the plants. Little Leaf purchases all of the various ingredients separately including nitrogen, phosphorus, potassium, and micronutrients, and then creates their own nutrient blend, carefully selecting each ratio.

They do not use any chemical pesticides, opting instead for more biological control. Insects which could cause problems include aphids and white flies, and one of their means to controlling this threat is through parasitic wasps which live within the greenhouse. The greenhouse is also "over pressure enclosed" so that when you exit the greenhouse through a door into the cutting room, you will confront a large burst of air, which is partially to keep the greenhouse cooler in the summer and all helps to prevent insects from flying into the greenhouse.

From the greenhouse, plants that are ready for harvesting move on a conveyor belt to the cutting machine, where air is blown to ensure the leaves are raised before cutting.

The leaves are sorted, and then maybe mixed, dependent on what is needed for the final product.

For supermarkets, the leafy greens are sent to a packaging machine, which places mixed greens into 5-ounce bags, which use 90% less plastic than some of the plastic "clamshells" used by other lettuce companies. The bags are then boxed, refrigerated and shipped out the next day. With California and Arizona lettuce, it will take a number of days to get trucked across the country. Little Leaf lettuce could be on your table the day after it is harvested.  In addition, harvesting, cutting and packaging at Little Leaf occurs in a matter of minutes. On a typical field-grown lettuce farm, the time from harvesting to packaging is probably measured more in hours.

For food service distribution, they sell four-pound bulk boxes, and this is one of the only times there is any human intervention, but even then, the employees wear gloves to maintain hygienic practices.

The trays which once held the harvested plants are emptied and then disinfected by steam so that they can be reused. And the process begins anew.

Check out Part 1
Check out Part 3